I'd wager he's not responding because nothing he could say would make any difference. I had to go through a similar process with myself and realize that I was a black hole of insecurity which instantly obliterated all expressions of reassurance or affection which other people sent my way. I realized that people could not win with me. They didn't even have a fighting chance. I had to start making conscious , judicious choices to trust people, make an effort to not let my insecurity be the master of my actions, and face the truth that though all relationships are temporary,that does not make them worthless. You can learn to do this too.