In a VERY awkward position with my friend!

[Dimentio]

Well me and my friend are both 15 and he is one of the two people i personally told i am gay, He was the nice one about it but is slowly getting further and further frome me :(
But i was looking at some 'Videos' And thought i saw him, So i watched it, And later realised, It was him, So without my friends seeing the rest of the video and just him with clothes on, I said "Isn't that (Friends Name)!?" They said DEFFINITLY! But in that video, He was Masturbating.
Now i feel awkward as he is my second closet friend, So should i confront him about it or should i just let him know i did not find it?
What would you do in my position?
Edit:
Hey guys, I need to add in this edit, It is kind of important, And it will help me, My friend started speaking to me in the morning, And i broke down in tears and said i had to go (It was on Facebook so he did not know i was crying), And now, I do not think i can look at him or talk to him again, All day i have been crying and feeling a HUGE regret and anger in me for watching the video and being turnt on by it, And also for that fact that, I cannot see my friend the same way again.
I now feel like the only friends i have is Internet friends as no one else speaks to me, I just been crying all day now because of him who was my last real life friend and also jsut from loosing him and seeing that video, I just cannot stop crying over it, I do not know what to do no more! My depression and anger is getting worse because of this, And like, I also have Selective Dyslexia but i do not like talking about it, I normally call it Dyslexia when i do, But it gets wrse when i am sad or angry, So i am shocked my writting is not too bad right now, but some of my PM's have been VERY bad.

[Donkey]

Think about it man. If you were a closet homosexual, would you want to know someone found you out? He hasn't told you for a reason and I suggest you just don't judge him for it and continue as if nothing changed. Sexuality shouldn't affect friendships

[DerBear]

Sexuality shouldn't affect friendships

It should not but It does a lot of the time, this is a shame, but it happens

[Dimentio]

Well like i said, He does know i am gay, And he is straight, I have seen the evidence for it, And techincally i am as only two people i know personally in real life know, I won't tell him, But it will be weird now, Like knowing what he has got going on down below, Thanks for the help though! :D same for Silver Wolf :D

[Gordo]

If you're close to him, I'd mention you saw someone that looked like him and that other people think it's him so he can take it down if he wants to. You'd be looking out for him. It shouldn't be weird for him knowing that you saw it because he posted it. Weird for you? I'm not sure what to make of that. idk why it's be weird for you.

As for him drifting away from you, friendships ebb and flow. They just do. I wouldn't think about that too much. You sexual interests are different, so he may be spending time differently than you and like any of us, like to spend time around people that have similar interests like team mates in sports or friends taking the same classes with same homework.

[Giles]

To be fair people, straight people, can and do post videos like that on the internet. A friend of mine done exactly the same and I'm fairly sure that he's straight. In your position I wouldn't do anything at all, leave things the way they are and if the friendship breaks down then that is that and it probably wouldn't have been too good continuing anyway.