Lack of confidence, ruining relationship

I thought I truly loved myself unconditionally before meeting my boyfriend, but now I doubt if any of that was real. We’ve been together for a year and a half and it was really a love at first sight situation because we clicked so well during our first date. A few months after starting our relationship I got pregnant and he moved me in his house right after.

Before the baby I was confident about us, but now since my body is changed and I feel useless since I’m not providing anything to the household since I’m a SAHM I’ve become REALLY insecure. Things that didn’t bother me before, annoys me now. For instance, he’s very friendly. If we’re out to dinner he makes sure to repeat the waiters name a few times just out of respect. He starts random conversations with employees checking out at the grocery store, etc. that’s just how he is. But now my mind has sort of twisted his actions to flirting, and that results in me blowing up on him about the situation. I know he doesn’t deserve that, but sometimes I just get so caught up in the moment and I can’t help but say something smart about how “flirtatious” he’s being. I know I’m causing unnecessary drama, and know we can’t live like this forever, and honestly I don’t want to. So my question to you guys is how do I gain my confidence back after a baby? Like seriously begin loving myself and my body for what it is?