Is the love gone for good?

Hi, My name is Jessica. I'm 23 years old and a hopeless romantic, If you make it through the whole thing, God Bless. Lol I have been off and on with my boyfriend, Justin (24 yrs old). When I first met him, I had those butterflies and I just knew that I wanted to be with this guy forever, I wanted to settle down get a house and have kids with him. I guess it was more lust than it was love. Well over the course of about two years we have been off and on. We fight over the little silly things and breakup, but then one of us always gives in and is the first to say "I miss you..." and bam! we're back together. Not even for a week and then it happens all over again. Well after our one break, it was just after his birthday which is on St.Patty's Day. I being a hopeless romantic or a loser lol I texted him saying I want to work things out, at this time it was around my birthday which is the first week of April. He agreed to meeting and we were set, that same night I went out with some friends to the local pub and I had run into some of his friends. They informed me how Justin was going to be a Dad, I fought back my tears and just forced a smile, saying "Gee that's great! Good for him." His friend, Paul said "Yeah I cant believe it either, it was his upstairs neighbor, he apparently helped her move in and well, you guys know the rest." I was hurt, upset almost sick to my stomach actually. I wanted him to be the father of my children one day, but I guess you can't plan everything to happen. Well we were still on to meet the night after that and we did. We talked and reminisced of all our good times. He came out and told me about the new baby on the way, I acted surprised (I couldn't tell him that I already knew). He said he, messed up and wished it was with me instead. I thought to myself, He couldn't even wait a few weeks to jump in bed with some girl he only knew for such a short time, instead of planning with me the girlfriend of two years?? Well we've been off and on again, since then and it has its ups and downs of course. But I'm really falling out of love with him, all we do is fight and it makes me unhappy everyday. Yet I miss him and I go back to him. I feel like he is still in contact with the baby-mama, but he won't own up to it. He's always on his cellphone and when I do ask he always says its his "Aunt" of which I have never met. I also cant stand it when he says he doesn't mind doing me little favors like running some errands, working on my car and even money issues. But the second he doesn't get his way, he throws it all up to me. I always say "If you were doing these favors to be nice and my boyfriend, then you have no right to throw it up to me.." I see other couples who I have gone to high school with, getting engaged, having babies and buying houses together. Not us, we can't even stay together for more than a week. I know that the heart and my head are telling me two different things. I am then left with this : " I love you, but I'm not in love with you anymore"..but it's how I feel. I've put so much time and energy into saving this relationship, I even did the bad by losing some very close friends because of him, because he had me choose. I'll never forgive myself but you got to keep moving forward. Is it worth the hurt and heartbreak to try to save it or is it time for me to just move on?