Oh, I know that the show's writers want us to be convinced that Sam loves Dean. It's just that they've often done a crappy job of convincing.

I haven't seen it for at least the last two years, and after season five, I'm pretty much convinced now that I was putting too much weight into a relationship that was never more than one-sided, and therefore nonexistent because there's no relationship with only one participant.

I've been reading a lot of meta after the finale in order to be convinced that everything which let me down last year wasn't as bad as it appeared to be, but it's a hard sell.