<human>: Condense the text into a few key points

I've been with him for a year and a half now. He was with his ex for about 3 years, then he was single for a year after their break up, before he met me. She's married with 2 babies now.

Thing is, he's still very friendly and social with his ex's family, primarily with her older sister and brothers. They still hang out, they're also very active on each others social medias, constantly liking / commenting etc. 

I'm not comfortable with it, but I don't want to force him to stop talking to anyone (even if I did, I'm sure he'll pick them over me) ....so how can I try to accept it? I'm the type of person who will keep thinking about it, letting it dwell but I don't want to..so gimme some advice please.
<bot>: Bf [26m] is good friends with his ex's family. I [26f] don't like it but how can I try to be ok with this?