Seeking expert testimony is a sign of strength. A personal relationship with a caring professional is proven clinically effective.
I believe that I can help with this situation.
Your very articulate and descriptive narrative painted a very clear picture of a somewhat self-indulgent, confused and depressed man who also suffers from sexual issues.
You did not mention anything about treatment or therapy for his various concerns, now or in the past, but this is a long-standing issue and will probably not change
It seems that he hardly missed a beat on his "social life" on FB once you deleted him, and he will survive without you at probably the same level as he does now, as long as someone will put up with his difficult ways.
You have chosen to end this relationship and say that you will not contact him. This seems like a strong and appropriate response. In order to truly put this relationship behind you, and help him to move on, I strongly urge you to ignore him, and underline that decision by blocking him from your email and phone. When the gates are closed he will have to give up eventually and move on to the next chapter of his life, as you will to yours.
Elliott, MAE, LPCC, NCC, CCMHC