Originally Posted by
atalose 
Yet you don't know any of his past history with friends or lovers like best friends would. There seems to be allot about this guy you don't know for being best friends.
And now you do, you know his cold hard truth and all that potential you fantasized about is gone. Like others have said, cut your losses, block him from continuing this toxic relationship and maybe try and figure out why you missed or ignored all the red flags.
I do know a fair bit about his past loves, and what went wrong , not so much friends, he is fairly introverted.
I expect he didn't want to really tell me a lot of things so as not to put me off either as a friend or a lover. Who wants to tell someone they have a massive alcohol problem. I just worked it out myself. I did know he drank a bit, but never saw a bad side while he was drunk before