Gay guy in need of relationship advice

Bare with me. There is a lot of important back story but I need help and I really don't know where to turn. Well, it all starts with a boy. We have been friends for nearly 6 years and the friendship is great. We are in the same close knit group of people and we see a lot of each other. But it can also be a curse. I really like this guy -- and have for nearly the extent of our friendship. We also work together for the same company but in seperate departments.Most of the time I have known his he was in a serious relationship so I never really thought I had a chance. He and his boyfriend seemed happy and I just pushed the thoughts of liking him away. But then they broke up and now there is nothing stopping my subconscious from going crazy for this guy.With any group of friends there is normal one-liners and poking fun at one another. I totally expect it. But he totally takes it to a different level in my opinion. Not to toot my own horn or anything but I have above average endowment that is pretty evident in anything I wear. He brings attention to it in our group of friends and even to complete strangers in some cases. It's one of the first things he mentions when he's introducing me to his friends I'm meeting for the first time. I try to take it all with a laugh.There are other instances where he might be flirting -- I'm terrible at figuring it out. I would have asked but there is one big thing that is stopping me. Before I met him 6 years ago, I slept with his brother (also gay). I was a regular hookup for about 6 months. So now Im stuck in this crazy love triangle. He and his brother have a pretty close relationship so I'm pretty certain he knows that part of history.There are other things that make me wonder. We have gone on vacations with a large group of our friends where he obviously had the opportunity to go back to a guy's hotel and hookup but skipped it to hangout me with and only me. We have shared a bed a couple times but no touching, cuddling, etc out of fear I'd pop wood and sorta expose my feelings.I need your help. I need an objective point of view and interpretation of whats going on.