Need advice

So I recently had a baby with my now ex boyfriend and I can’t help but feel some type of way because he claimed that he loved me we were together for my whole pregnancy and and before I even got pregnant (btw he purposely got me pregnant and told me later on when i was 7 months pregnant) and our daughter isn’t even 2 months and he already has a new girlfriend and my body hasn’t been back to Normal yet. Our breakup was mostly because he didn’t get the last name and my postpartum depression and now I feel like my postpartum depression is getting worst because I’m getting more and more insecure of how I look and how my body looks. I just wanted to vent since I have no one to talk to about it. Any advice on how I can move on from him? And should I be petty and put him on child support since he doesn’t even see his daughter?