cold feet?

LUKE: It's not biologically natural for people to mate for life. Animals don't mate for life. Well, ducks do, but who the hell cares what ducks do?

LUKE: I mean, people grow and evolve their whole lives. The chances that you're gonna grow and evolve at the same rate as someone else...too slim to take. The minute you say 'I do', you're sticking yourself in a tiny little box for the rest of your life. But hey, at least you had a party first, right?