Husband in love with someone else, is there hope?

Hello all,
This is pretty involved so I will try to keep it short. I will just start from the beginning as I don't know how else to reconstruct this whole mess.
Six years ago my husband and I were married. he was 25, I was 20 at the time. I was his 3rd wife. I love him more than anything. I still look at him and feel intense love, I will can't wait to see him everyday after work, I still feel "in love" with him. Anyway, we were married and things were kind of off from the start. Andy was obsessed with porno beyond what I'd considered normal limits but eventually I accepted it and actually got into it a little with him. But then he was also overly flirty with friends and family and I started getting lots of comments about it. One major problem we had was a crush on my little sister. This created a lot of friction in our marriage. He'd act like it was a joke but I knew otherwise and this hurt me tremendously. It got to the point where she hated him for his actions and I resented my sister. When I'd confront him he'd act like I was being petty and so I'd drop it and just keep in my anger. Anyway, there were a few other things that bothered me but I won't list it all. He'd get phone numbers, even took some girls to lunch. Over time I started to feel more and more anger and hurt towards Andy. I felt that the reasons he acted the way he did was because I was not enough for him. I would look at the way he flirted with my friends and with he'd do the same things with me. Stupid stuff like calling them "baby" or touching them in sweet little ways that he'd never do for me. Andy never acted interested in me. Everything he did was great and wonderful but to discuss something about me was never done. He would act bored or uninterested. Eventually I found friendship with an ex of my sisters. It was seriously nothing more than a friendship starting out. He'd listen to what I said when Andy wouldn't and we actually had fun together. Anyway, one night he came over and we were drinking, Andy was gone, and my friend came onto me. It was nothing more than a kiss before I stopped it but I still feel so responsible. I ended our friendship immediately and wanted to tell Andy so bad but I knew he'd leave me over it, it's the way he is. Anyway, time passed and I kept in this guilt of what had happened. I told only one person, my best friend. Things were still not that great with Andy. He only acted interested in me when we'd have sex. I mean don't get me wrong, it wasn't bad all the time but he just wasn't an overly loving husband, I just started to try to accept this as the "way he is". But with time I felt so inadequate. My best friend and her husband started dropping innuendos about "sharing" and "swapping" and although I wasn't into any of that the innuendos were kind of fun. I thought maybe these were the kind of things Andy needed to make marriage good for him. It is a stupid thought I know but I really did feel that way. So, we messed around a little, my friend and I got topless in front of our men, we skinny dipped, nothing more though. I thought doing these things would make Andy see me as the coolest wife in the world. WRONG! He got mad and weirded out. I apologized and told him my line of thinking but he seemed to never get over it. I never felt so stupid in my life, I really thought maybe that's what he wanted. He always joked about that kind of thing anyway until the point where I thought he was serious. Anyway, more time passed, about a year and nothing else like that happened. I thought things were back to some kind of a normal for us but then I found out last December that we are pregnant with a second child. I was on the pill and it was totally NOT planned as we both knew we only wanted our first born but still Andy accuses me of doing it purposely. I had never felt so bad ever, I didn't want to be pregnant any more than he wanted me to be. I needed him more than ever and he was just running from the issue. With time I noticed him drifting away. He would be at home but still seem like his mind was somewhere else. Then I find him talking secretly to my best friend, the one mentioned earlier. I never did mind them being friends but it hurt that he acted the way he did. He'd hide in his car to talk to her or take her to lunch during the day. Finally after weeks and weeks of my asking and him denying that there was anything going on her husband called and asked to talk to Andy. When they got off the phone Andy left until that night. When he came home he explained to me that Michele had confessed to her husband that she loved my husband. I was so hurt at hearing this. I asked Andy right then if he wanted to leave or stay and work this out and he wanted to stay. He said he was sorry and swore it was over. Well things were great until a week or so later when I saw her number on his cell phone. Turns out they had never stopped talking. The whole thing started up again and we'd play some stupid game where I'd ask Andy to stop, he'd say he would and that we'd work this out, and then I'd find out otherwise. I know at this point you are all thinking, "How stupid is she?" but I DO love him, not to mention being pregnant makes it harder. So this kept on and then due to the stress I started having complications in my pregnancy. On June 10th, one month before my due date AND on Andy's birthday, my Dr decided to do an emergency induction because the baby had stopped growing. I called Andy and he came to the hospital. He held me and said he was sorry, we'd work it out, he knew we could, etc. He said everything would be ok. Well, Drew was born and things still weren't ok. He even almost missed his sons birth and later when I get the phone bill I find out it was because he was downstairs talking to her!!!! I was so heartbroken. There were also complications with the baby and I had to stay at the hospital for 5 days. I saw on the phone bill where on the nights we would NOT stay and keep me company he was talking to her for hours! So, I finally start to accept the fact that there is no changing him. But then he still wants to stay. I can't understand it. So I give him chances again and again. Then one day I stop in for a surprise visit to his office and he is talking to her on the phone. I just walked out. He followed me and I told him I didn't understand why he tells me he wants to stay home but continues to do this. He is hugging me telling me he loves me etc, he is sorry, blah blah blah. So then he calls me later that evening and says, "Look, you really don't have to worry anymore, it is over". I actually believed him that time! He comes home and kisses me, I mean he hasn't touched me in months and we are making out on the couch. The next day he asks for oral sex. It really seemed like things were better. THEN........the phone rang late one night. I was asleep on the couch and woke up to the end of the conversation. It was a simple conversation. I heard Andy say, "Oh, ok. well, we'll talk to ya later" and hang up. I asked who it was, "Michele" he says, "Oh" I say. For some reason I didn't care, lol. Maybe I was still asleep. "Did she want to talk to me?" I ask. "No" he said. Still I just say ok. So a little later I walk out into his computer room to get something and he says, "Don't you want to know what she wanted", I still can't believe he even brought it up. So I told him sure. So he tells me that Micheles husband is on a rampage and might be coming over to confront Andy. STILL I was clueless. Then he went on to tell me that Michele told her husband that she was leaving him to be with Andy and the reason she called was to tell Andy this so he could in turn tell me the same. I couldn't believe it. So then Andy tells me that no he wasn't planning on doing the same thing and he has NO IDEA where she gets the idea, lol. So anyway, I am sick of it at this point and the next day I call Michele. I told her I am sick of the lying and I wanted to talk to her to see what we are both being told because I suspect we are both being lied to. So she goes on to explain to me that her and Andy have been planning for sometime to leave each of their spouses for each other and live in an apartment together. She tells me that Andy has told her that I was aware of this!!! So I tell her my side which is that Andy has told me he does not want to leave and I of course don't forget to mention the oral sex and kissing. She was pretty put out by that since apparently Andy has told her he hasn't touched me in months. So it seems we are both getting lied to by him and I point this out to her. I finally decide to confront Andy and tell him it's her or me, what do you want. For three days I put up with, "I don't know what I want". He would explain to me that he does love me but that he is "in love" with her and that when he is home he is only thinking of her. I even heard from my six year old that he called her in front of her and said things like, "I love you" and "we will always be together". It hurt to hear all of this but I needed to know it. They both tell me there has been no sex, I don't know if I believe it or not. He does confess to kissing. So after three days of hearing that he didn't know what he wanted I told him that his time was up and the decision was out of his hands. As much as I love him I cannot endure this pain anymore. I told him that I would file for divorce and get this over with. I told him that he could always see the kids and that I would not kick him out until he could get his own place and a new office<he shares with my dad now>. I felt like telling him these things would not give him any other reasons to want to stay. Well, suddenly he wants to "try" to fix this. He says it is hard but he would try to forget about her and work on us. Also, apparently to score points for herself my ex friend told Andy about my kiss incident. Which I am glad, at least it's out now and I have no secrets, but now that is his excuse for all of this even though it was going on well before he knew about it. Anyway, I want to believe him but I don't know. I know you all think I am an idiot at this point, I just don't want to see him go. I DO love him and I miss him so much. Despite everything I always loved him. We have discussed our problems past and present and have both said we are sorry but I don't know if there is still hope. I guess what I am wondering is that after all of this can a marriage and SHOULD a marriage still be saved? I took my vows seriously and even he says he does not want another divorce nor break up our family. He says he does still love me but that right now he can't get his heart away from her. What do we do? I am so upset over this. I really do love him. Everyone keeps saying, "get rid of him!" "he's a jerk" etc but I only wish it could be that easy. What do we do?
DipityDane.