Bf still friends with his ex FWB

Well he actually hardly talks to her anymore but he’s in a group with her and they talk on there sometimes. She also sends him texts every once in awhile, which he says are just memes.

She was/is in love with him for years but he says he never felt that way back. She went to his place crying when she found out about us dating.

I had a FWB and my bf was so pissy and jealous when he texted me twice. My bf says it’s different because he and his ex FWB are in a group together.

I tried being friends with his ex FWB but I keep thinking about them together (him getting a boner for her etc.) and I just get annoyed. And now I feel even worse because after trying to be her friend (and I really thought we were friends), I feel like she’s not wanting to be my friend.

It’s just getting me so upset that there’s any type of communication between them when I know he would NOT be ok with it if the tables were turned.

I’m not sure what I’m expecting by putting this out there because I know some of you will say to just break up with him, but I won’t. Maybe I’m hoping to hear others with similar stories and how it went with them?