Tryng to co-parent long story.

So a little back story I think is best. The father of my children ( referred to as s.d. is this post) we were together 8 years, and had 2 boys together. We split due to it not being safe. I put a protection from abuse order on him a little over 3 years ago. He met a woman 6 mo after we split up, knocked her up n put a ring on it🤣. Well they split after the kid was 6 mo. They were both crazy and volatile, he told me his side. I never liked having her around the kids as at their house their was only 2 rooms theirs and their baby's my kids slept on the couch, and she used to talk to them and treat them like shit, my kids words and his words. Well The last year that they have been split up we have been communicating about the kids through email (per his request when we went back to court, it was through his mom prior ) well it's been going great sense they split, he has been seeing them every weekend and more if he asks or I ask. He has been paying child support and started paying tward the back child support. I knew it was too good to be true! I started thinking maybe he had changed, maybe we could share custody. I was excited for my kids to finally have the dad they deserved. Well last week a friend of mine who is a mutual friend of his and hers. Sent me a screen shot of their fb profiles. They are dating again. I asked him if they were together he said no. Well he fessed up the other day and said they are trying to make it work. 🤦‍♀️I asked my oldest who is almost 6 how he feels about daddy dating so and so again. He said well daddy doesnt love her, she isnt nice to us. I, at this point feel like maybe I shouldn't have asked because I'm pissed. Well I'm furious. And now child support has stopped. Its through the state at this point so that means he quit his job again!!! Which he did every 3 or 4 weeks when they were together, so the state didnt take his check for back child support. I'm blown away honestly. I thought he was getting his life back on track, and doing good honestly. But here she comes and there the boys father goes. 😫 at this point we have to go back to court for parental rights and responsibilities before next april as the pfa runs out then, but I'm thinking at this point should I just go now for full custody and get it over with, or give him chance number 92397590769754637279.