My boyfriend still talks to his first love :/

Last night I was at my boyfriends and we were just chilling on our phones and I happened to look up and see who his recent people are that he talks to, and I saw his exes name at the top and I was kind of like oh
I'm not going to be that girl that is like wtf you can't talk to her, but because I know they have history it kind of bugs me, like a first love is a huge kind of thing... And if you still talk to them then yous would share a lot of information so I'm not sure how to feel