BOTH WERE MARRIED BEFORE AFFAIR BEGAN, 2 YEARS AGO

Hi, I could do with some advice. Manager from work over 2 years ago started flirting with me. It was nice to have the attention, I have been married for 25 years (got married at 18), and just lost my father to cancer (no excuses). I must have been such an easy target. Anyway, the flirting and phones call etc. went on for 5 months, I never gave him my mobile number in all this time as I did not want contact outside of work. We both agreed that it was nothing serious & if either one of us wanted out we would say so no hard feelings & remain friends. I was good with this, so then it progressed. Then a week before his 38th birthday we finally had sex (after hours in work), it was amazing (I know now why it felt like this, nothing more than hormones etc.). After this we kinda got closer without noticing. This was in the September, then in between this time & the next (which was December), I think he thought things were going to fast & he got scared, he started talking about his wife more & telling me things about her (I never asked), he never even knew my husbands name & still doesn't as far as I am aware. Then he went distant on me for 9 weeks and then one day he rang me after been away on a trip & said he missed his family whilst he away & this made him realise how much he loved them, but he still had "thoughts" about me. I said no problem, I understand & left it at that. Then two days later (I had given him my mobile in mid-oct), he texted me and said he missed me & I am a great friend, I replied & said I missed him, then it went from there. Between Dec & Jan we did not really speak as it was Christmas then when we got back to work in the Jan, we had sex again, then he went away again with work, so the next time was Feb and this was the last time. When he came back work after the last time he went really distant with me, did not call me or reply to messages for days. This went on for 3 months, it was really confusing & hard for me, I didn't understand why, he never explained and just said he still wanted me. Then in the June he rang me and told me he was leaving his wife. Now this was a year ago and between then & now what a roller coaster he has had me one. He wanted me around, he wanted to be friends, he still thought about me etc. I now feel nothing but anger towards him, he is single now & god you can tell, this is when he realised I was no good as I was still married he chased me for years before we started flirting always the case, you fall for them then when they get you they drop you. I finally 5 weeks ago sent him a message that I am over this thing between you & I, he just replied no worries & I hope you are ok. Since then I have avoided him, not spoken to him unless he says Hi, I just reply with Hi back, but the past week he keeps showing up in places were he knows I will & trying to talk to me. I don't get it, is it because he feels like an arse for the way he treated me? Or, he feels awkward because we work together. I know I am not innocent in all this, believe me I have gone through extreme unhappiness, depression, 15kgs, crying & know I just feel empty and worthless. I love my husband but I am not in love with him, I know now I did not love my AP, but was in lust with the thrill of it all. But I cannot stop thinking about him (not sexual), just how a man I thought was decent could hurt somebody who he says "I am the nicest person he has ever met, I have a good heart & an he loves this about me". What a fool!! Sorry for the long message, I hope somebody reads this & replies to me. Thank you.