Is it normal for a guy to talk sometimes about his exes??

I can be jealous and that's why I ask because I don't want to overthink or whatever 😂

We are at different places atm for holidays and he texted me there was a random high school reunion of his class (we're 22) so he went and told me that was weird to see all these people and his first girlfriend. And he learnt that she lives just the building in front of his now.

I mean...why telling me that?? He just sent me that text about his ex living next to him and that's it...what's the point?? Also he knows I don't like when he talks about exes even tho I try to not be too jealous and paranoid ahah