What Makes a Relationship

I emailed a certain someone the other day hoping that we could make peace and be friends. Today I got a reply that he really liked talking to me so long as we were dating, but now, as "just friends" there's nothing much to talk about. He doesn't even want to be around me unless we are dating. What is that supposed to mean? It really makes me wonder about how we were. Did he ever really care about what I had to say? If he can't find anything to say to me now, then how could he ever have said that he loved me? Does kissing versus not kissing a guy really make that much of a difference in the enjoyment of conversation?
From now on, all my relationships will begin as friendships - this is in the hope that I can still have someone to speak to when all is said and done. He used to be a source of comfort, someone I can hug when I feel like crying. And now I have no one.