I feel so betrayed

So my ex bf moved in with me when I was 9 months pregnant so I wouldn’t be alone in case I went into labor. We were dating at this time. Everything was perfect. We had our ups and downs. When I first found out I was pregnant he left me and pressured me into an abortion for months. But he came around apologizing and it seemed so sincere so I slowly let him back in for the sake of my son. As months passed he was telling me how he wants to marry me and keep me forever. He just seemed so kind and loving.

Then at 40 weeks I got induced for high bp and migraines. I noticed in the hospital he wasn’t very caring towards me. During my contractions he fell asleep instead of helping me through it. Once baby was here he was constantly on his phone, until a nurse walked in and then he was so attentive. It felt like a show. Then once we went home with baby, about a week and a half into it, he seemed like he didn’t care about me at all.

His mother who wanted me to get an abortion is now overly obsessed with my child. I told him I just need some time to recover physically and adjust to a newborn and an apology from her would help. (She did meet the baby). He told his mother and she started crying to him and that’s when it all went downhill. I wasn’t even out of the hospital a week.

He immediately took the side of his mother who he’s weirdly close to. She hated that he moved in with me and while living with me, he called her at least 8 times a day and texted her constantly. I had to check and see it was his mother’s number because it was so excessive. I never said anything though because I didn’t want to fight even though I found it strange.

Two days ago he left. He told me that he was using me and leading me on this whole time just fo get what he wanted from his son. And that he doesn’t want to marry me and he will happily take me to court to try and get as much custody as he can. He said I made him so miserable when all we did was laugh and have a good time together. I just feel so betrayed and like I lost my best friend. Who turns out, really wasn’t my best friend. I can’t believe he left before my baby is even two weeks old.