I'm real good at the selective noticing thing myself. "why don't you ever...?" "But I did; this time and that time and the other time ..." (sheepishly) "Oh."

For me, this isn't limited to people I'm not "close enough" to. I can even forget things important to my SO -- the saving grace is that he's usually there to remind me. YMMV.

IMHO, reasonable expectations are DEFINITELY key. It can often work best to have no expectations at all, if you can manage it. That way, anything negative that happens is interesting, and anything positive that happens is serendipity.