What should I do?

So I found out a while ago I’m pregnant again. With my third baby. It would be my third baby with the same man. However, him and I have been broken up for about a year now. We really have never stopped sleeping together after we broke up. And of course we have maintained a pretty decent relationship so our kids don’t see us hating each other. And really, I could never hate the man that gave me the gorgeous kids I have today. Anyways, more to the point now. I’m almost 12 weeks pregnant and since I have told my bd that I am pregnant again he of course questioned if it even was his. And based on the fact I haven’t slept with anyone else, I’d say I’m pretty damn sure it’s his. But he has also begged me to get an abortion. He also did this when I found out I was pregnant with my 2nd and everything turned out fine and he’s a perfect and healthy little boy now. I added that we have broke up because his reasoning in the abortion is because he wanted us to completely start fresh with our relationship and move forward and now he feels like the stress of another baby will be too much for us to start over. He has moved back into the same town as me and his kids and started a new job closer as well. With moving expenses and the kids we already have, we are tight on money right now. But here’s where it really gets messed up. He’s asking me to get an abortion so we can start our life over together again. And he knows I’ve wanted to just restart ever since we’ve broken up so it really makes me nervous he’s only telling me these things to get me to have the abortion and then just kinda leave me in the dirt again. He’s home so far as to treat me horribly and talk to other girls since I’ve told him I was pregnant but as soon as I told him I had been considering an abortion he tells me he will cut all these girls off and we can start fresh, just the 2 of us. And I do so so so so badly want to start over and just be happy with him again without worrying about other women being around my children but I also feel so so wrong for (potentially) getting an abortion. I literally have no idea what to do at this point. I don’t know if I say fuck it and be selfish for me, for something that may not even work out again anyways or also be selfish and keep the baby but constantly worrying if another woman is around my kids or is going to show up to the birth of my next kid. I just really wish there were a way to figure things out so I could keep my baby and also just start a new life with the man I have given my whole life up for, for the past 5 years, and for the 2 kids he already gave me.

I really really really don’t want to hear the negative because trust me my head is already telling me that 24/7. I really just need the people who understand the situation. Because really, I feel so alone and like no one understands at all.