Damn stack sizes

[soah]

Party 2/4 6-max

Guy that plays every hand (badly) limps in, I raise to $18 in the CO with AKo. Button who starts with $81 calls. All others fold. I have been usually overlimping or folding behind the guy who plays every hand but not raising him much (their postflop play in limped pots was so poor that I saw no need to isolate without strong hands). The button's call caught me by surprise. He may be shortstacked but he wasn't spashing around a lot.

So it's HU to the flop with $44 (after the rake) in the pot and he has $63 left. I miss the flop. What am I supposed to do here? Is check/folding here wrong? Betting and folding to a raise.... is wrong? Getting all my money in the pot here.... seems wrong? It's been a long time since I've been so confused over such a simple hand.