This "I gave up looking for you because I hit a dog and the mean vet lady who yelled at me really turned me on and made me want that normal apple pie life I gave up on Seasons ago" motivation for Sam is beyond lame. Again, maybe they'll come up with something that makes more sense, but we'll see.
I agree. I'm really unhappy with the idea that Sam just abandoned Dean and went to a farmer's market. Really unhappy
Personally, I don't care that Sam didn't try to help Kevin. The kid may be important to the myth arch but he's kinda "meh" to me, so whatever. I could probably rationalize him not looking for Cas, in a "Cas is an angel and he'll be fine and maybe I'm still a little pissed at him" kinda way. I could even accept Sam being unable to find Dean and giving up in dispair, sort of like he did in season 4. I didn't like most of season 4, but fine. I'll deal.
My point is, I know I can get (and have gotten) over a lot of sketchy behavior from these characters. I could do it, again. But Sam just not looking for Dean, at all
and not even feeling bad about it... No. I don't think I can get passed that. Not if the show wants to keep up any pretense of a brotherly bond.
I want them to make those misty watercolored memories of Dr. Birthday Cake some kind of monster mind-fuck or heavenly mirage or something
that explains why Sam didn't search for his missing brother. Otherwise what's the point of being invested in Sam and Dean's relationship?