I'm the type of guy who can listen to someone, but once once they start talking about themselves, my attention span quickly turns to zero. Now I'm a polite guy, so I will look like I'm paying attention but in my mind I'm in Latvia and I spurt out responses like 'yeah' or a small laugh.

For example, I have this buddy who likes to talk, he likes to talk about himself and have the whole group listening to him over everyone else. He isn't an asshole, it's just the way he is, and when he talks to me about shit I don't have any interest in, I'm not sure how to respond.

It's a general problem I find with me, like if I'm in a group I don't feel like I have to show my attention to the pointless/boring stuff as other people are there giving their attention, but in a one on one I struggle to deal with it and just find myself giving fake interest to make it look like I'm enjoying the conversation even if not.

TL;DR

Low attention span when people talk about themselves or pointless stuff, how to come off as not giving too much attention but without looking like a c*** or giving a bad vibe.