SuperB
I'll shoot from the Hip anyway....
I would suggest you do the following, grab a couple of mates and hit the town. First sexy single guy you see.... Make conversation and get hooked up. The problem you're having is self confidence. You've been with you Ex for a couple of years I take it. You now feel that you can't go out and meet new people. YOU ARE VERY WRONG!.
Leave the useless mother. He has another woman, that is why he tries to see you as little as possible. He just wants to make you think there is hope so you don’t go and do something stupid to yourself.
GO OUT AND GET LAID ! Find the love of your life, have kids and live happily ever after

I can hook you up with nice, descent guys if you want
Come to think of it, My brother in-law needs a new GF, I hate his wife and he is in the process of getting devorced