He was gonna cheat on me? (Long story I’m sorry) opinions?

Ok to give a little backstory We’re 17. We’ve gone to different schools because his mom doesn’t like public school but now I’ve been homeschooled this passed year due to past family issues. We have been together for 2 years now. also I’m pregnant.. I know stupid. 15 weeks 🤷‍♀️ keeping it and he’s super exited. He was exited since the second I told him. Not one moment of sadness or regret about my pregnancy on his part.

In the beginning of our relationship neither of us took each other seriously. It was till about 4 or 5 months in we really made a connection and started focusing a bit more on each other. But he would constantly post other girls and he was always on their stories and stuff. Taking them places and obviously flirting right in front of me. It hurt pretty bad so I guess I looked for acceptance elsewhere. I talked to some guys just over the phone that lived in some other states but I had talked to before I dated my current bf. Just for the compliments and reassurance since I felt like I wasn’t enough for him. I stopped pretty quickly even though it wasn’t anything sexual it was just conversations I felt guilty. My boyfriend has this tick I guess where he literally tells me everything. If he has something on his mind he gets really fidgety and weird and has to just blurt out what he’s thinking about if he feels it’s wrong. He’s told me he’s had a lot of sexual dreams with a bunch of girls in his classes. He’s called me crying when he wakes up because he felt bad he had another dream. He had a bunch of thoughts about them. This was about a year ago though and it eventually all stopped. Well when he was going into 12th grade he was supposed to car pull with one of those girls. Just them two in her car. I was fine with it I trust him. They planned this throughout the whole summer but it ended up not happening because she didn’t get her license. He eventually stopped talking to her and all the other girls and admitted he liked them and was flirting and stuff.

About a week ago he admitted to me out of no where “honestly if Sam would’ve taken me to school i would’ve cheated on you🤦🏽‍♂️” at first I was like well damn ok w.e it was a few months ago. But yesterday I really started thinking. If I would’ve said “I would’ve cheated on you with so&so” he would’ve gotten really mad at me and probably not even talked to me for a few days.

Now I’m super upset about it. Like he really would’ve cheated on me after he told me over and over I could trust him riding with her. And now he’s telling me he would’ve fucked her.

My question for you is do I really have a right to be mad at this ? What would you guys do? I know we’re really young but I do love him. He’s honestly everything to me and I know he feels the same. It just hurts so bad thinking he would’ve had sex with her and honestly I’m repulsed by him now. For me just the thought of touching another guy like that makes me wanna throw up. And he still goes to school with this girl and sees her everyday. Idk. What would you think/do?