They should read between the lines more then. Even when they were fighting for that short time, it was obvious to me he cared about her, in that he always seemed to be looking out for her, and stuff like that. The coma was more of a regret of not showing it more than anything. It was like "I'm not going to get close to anyone, so when something happens it can't hurt me" only to realize it isn't that easy.
I remember doing a full article on how I felt the relationship was handled, and I may posted it again (possibley rewritten to my current style), and it certainly shows that he didn't start caring after the coma, but long before that.