need to vent

Hello all! so basically I'm just posting this because I need to vent to people I don't know... so my ex and I were together for 3 1/2 years. throughout the years he cheated on me several times, but I loved him so I stayed, we'll then I found out I was pregnant august of 2014. I had my son April 2015 and again found out he cheated on me through my pregnancy and after we had my son. I stated to try and make things work. well we were doing good and then went through a rough patch he ended up wanting to take a break about 2 months ago because he felt he wasn't happy anymore and didn't know if he wanted to commit to me forever or if he could commit to only me. well over that time waiting I was so depressed but not I'm starting to get over it and I'm realizing I have little feelings left for him because all that he has done to me. now of course he realizes he made a mistake and is doing everything possible to win me back but I don't want to anymore.. of course I will always love him and have so many memories of us and of course our son but I don't think I can go back. he keeps telling me I'm breaking him. am I wrong for not wanting to go back... I have tried so hard over the years to make things work but now that he realized it's too late for me...but it still kills me inside.