This may have already been said, and probably far more eloquently, but I DO believe that Quentin loves Jamison. It's just that he doesn't understand that loving someone is an active thing, it isn't just how you feel. At this stage of the game, and for quite a bit of the 1897 storyline, I think Quentin is just too selfish and immature to recognize that loving Jamison *obligates* him to look out for Jamison's welfare before his own. But of course, when dealing with a vampire cousin, an evil Phoenix, hostile gypsies, a crazy wife, a werewolf curse, and assorted female cuties it's hard to put someone else's needs before one's own.
I think also that in the 19th century, it probably wasn't uncommon for children to be treated much worse than Jamison is treated by Edward, Quentin, whomever. The way the Reverend G. Trask deals with Jamison is more in line with my understanding of how many children were treated 100+ years ago. Don't get me wrong - any child deserves better! Then too, the Collins family WAS always a little...how shall we say...dysfunctional?