I'm not suggesting Shawn should have lied to her, and I get why he didn't. But the way he went about it was hamfistedly awful. He didn't really answer anything, he looked like he was dodging instead of being honest. He led her to draw whatever conclusions she wanted or feared, instead of drawing them up. He didn't try to calm the situation down at all and answer things more plainly. I dunno. It just seemed like he handled it poorly, even for what he was trying to do. I am also curious why he had that in his tux coat pocket, when that's not what he was wearing when they busted into dude's room, and didn't seem to be on his mind when he was on the way to the wedding, given that he needed the sign to prompt his memory of it.