I totally understand how you feel. my d has been over a while and the good news is that I am now remarried (with new baby!). I too, have a 7 year old with ex h and he has turned out to be a horrible father. he had an affair (pre-bomb/led to bomb) and guess what? after the thing was exposed and he moved out and they could "freely" be a couple, the thing lasted all of 2 months!
and that year-long sep. was vvery hard on me and my daughter. i never thought I would meet anyone. I thought I would bhe alone even though I am attractive, smart, etc. I thought, who would want me with a kid and all that jazz? well, I met my current h and guess what? he adores me AND my daughter. my point is, don't worry how things will play out, they just WILL. I could have never have predicted things EVER getting better when I sat in our (ex and my) house ALONE night after night. I thought my life was "over".
I am so much happier now. ex h truly wasn't the person for me and I knew this LONG before heleft, but I couldn't admit it to myself. my family saw it, so did friends. I was depressed for a long time. he was never there for me emmotionally in any way. I was truly alone in that marriage.
but I DO get the jealousy part.. he is now living with someone 15 years younger (I don'tknow why this bothers me) aned I felt a bit of jealously when I found out they were taking my daughter to a familyfunction of his (big Italian family that I was very close to) andit kind of hit me. but my therapist told methat is a naturalfeeling even though I am happily remarried. you don't just "turn love off", so to speak. I am not "inlove" with ex anymore, but it's stuff likethe memories with his family and such that sometmes get me. BUT, it gets easier over time and you WILL find life with someone -- just build a great life for you and your child and you will be amazed at where you will be months or a year from now. it happened to me.