He's not a complete nutjob, he just has a finely calibrated sense of paranoia! That time he saw ghosts, oh, a couple of weeks ago, doesn't count.

"No, sorry, I've never seen you before. And I'm not famous, I'm just a sniper, that's all. Are... are you famous?" Not that he'd drool over her even if he did. She's young enough to be his daughter!