I know how he feels. My best friend and I were in the same situation. I am the guy and the way I saw it was a way of showing my love for her. I don't mean it as a passionate I want to marry you love, but as a I know you'll always be there for me and I don't want you to ever go away type love. Be honest with the man, tell him you care about him deeply but that by doing that it may wreck your friendship.