I just need to know what I should do?

I'm 18 and I am a gay male. Since the age of 13 I developed strong feelings for a friend of mine at high school, which have, unfortunately, grown stronger since and its almost at the point where it is unbearable to keep it from him. I don't know if i should tell him or not.

I value him as a friend and we get on really well. My concerns are that firstly he may not be Bisexual or Gay, or if on the odd chance he actually is, that he doesn't feel the same way, or also if i was to tell him, how he would take it, or accept it. I don't want to make things awkward between me and him, and i've tried to "Get over" him in the past but its just impossible. I can't seem to control these feelings of attraction.

Its not purely based on looks but it's his character too. I just dont know if i should tell him or not. But ive had to keep it from him for the past 5 years and its extremely difficult and i struggle. I can't bottle my emotions in and this is one thing i've had to keep locked away.

Every relationship i've had (with the exception of 1) I've all been hurt in. Wether it be cheating or otherwise, all i've been hurt or damaged in. The best relationship i have had ended abruptly as he was killed in a road accident 3 years ago, and i've not found anyone caring enough since. I just feel he could fill that void.

I have a terrible feeling of guilt, knowing i shouldnt feel this way about a friend, but also because i've not told him. And also a terrible feeling of awkwardness. I just need to know what i should do!