Could it be as simple as you have created a magical fantasy Jerry and Elaine friendship with this guy. slept with him and you took it to a whole other level and made him your everything. You didn't want to give up that fantasy, reality is to painful to accept so you gave him a second chance to prove to you again that he is not that into you like you are into him.
Friendship- lover what ever term YOU wish to use the fact remains, you don't even know where this person lives.
You can make what ever excuse you want, he drinks, he's drunk, on a bender, he's mad at you for not allowing him to move in with you, ect. ect, to ease the pain and fend off accepting the reality but you can't run from that reality for very long, it catches up quick.
Your obsession with him should be a big red flag that something inside of you is not thinking clearly or behaving healthy.