Jealous of his Ex?

My boyfriend has been with over 30 women sexually, we both of a high body count, that doesn’t bug us.

There’s a girl he’s friends on Facebook with that was a serious girlfriend, 2015-2017, and they knew eachother before that.

They were close friends that dated, and I imagine we’re eachothers firsts.

She knew his family, they got a dog together, and they seemed really happy.

I recently learned that she cheated on him multiple times and that’s why things ended, obviously she wasn’t perfect.

Still, I can’t help but feel jealous?

I just seen him and how different he was with her than me, but I also know they most likely weren’t happy.

She also kinda looks like me which makes me a little uncomfortable, and also, they are still friends on Facebook.

He’s never give. Any indication he’d cheat, but something about him being with her, knowing they were so serious, and then it ended like that scares me.

Another girl he dated, on their”in a relationship status” it was so many people going “finally! I knew it!”

Where as with us we went out a month then he asked me to be his.

It just seems like all these girls were close with him and his family for a while when they started dating and I wasn’t.

I know it shouldn’t bug me, but I feel weird, like I’m missing something. We’ve been together 9 months, and any idea of becoming more serious, like moving in together, an animal, even marriage, are shot down. It kinda freaks me out.

UPDATE:

He’s informed me numerous times he finds sternum tattoos hot and I just discovered his ex also had one.