Friends boyfriend might be gay?

Ooookayyy so to start with I am male (18) and this friend of mines that I have known for a little over year and a half has boyfriend (both 1 year older than I am).

So the story pretty much starts from when I came to my current school. I saw my friend's boyfriend (Let's call him Mike) (I wasn't friends with her back then) from time to time at the school corridors and I was like daaam that guy is hot.

So nothing never happened we never said anything to each other just quickly looked at each other when we walked by each other.

So that is the easy part, I meet a guy, I have no idea who he is and he stares at me and I stare at him and I think "okay, he might be gay or not (I have bad experience judging on gazes whether some one is gay or not).

Well it got tricky when I met Mike's girlfriend (Let's call her Alice) (I did not know they were seeing each other) and I became friends with Alice. So we were friends for like a month or two and then I found out that Mike and Alice were together when we had this one group chat in the corridor. And I was like "waaaat? I was almost sure that guy was gay".

So as time kept going I started to notice that every time I appear and go talk to Alice and Mike is nearby or also talking to her, he just makes some excuse or goes to toilet or just leaves. And I got the feeling he is avoiding me or something. Even tho when we walked by each other (me and Mike) we still would just look at each other.

So the holidays came and school ended and I didn't met neither Alice nor Mike for a long long time. Until today again. Alice and Mike were at school to get results from the tests and I went speaking to them (there were also other people) and I was standing in front of Mike and then I notice that he is just staring at me (not too visibly but like sneaky-peaky like) and then I just look back at him and we look each other for several seconds until we broke our gaze and then I have to go to lesson.

So this again confused me more about if Mike is gay or not. I do not really know what to do (probably I should do nothing) but I have no idea how to read other people's messages when g.e. Mike stares at me, avoids me when other people are around and then silently stares at me more and... I have no idea what to do or how I should think about Mike and Alice?

Sorry for such long and boring post. My first post ever (!)

 

Yeah well I also thought about if he is some guy wanting to beat me up but it sounds quite insane as he has no idea I am gay (no one does, except one close friend)

Also when he yesterday looked at me he looked desperate (I have no idea why I got that feeling but I still did get it). Also he does smile at me when we walk by each other and stuff.

On the other hand why the hell does he leave every time I appear when some one else is around?