500 days of Summer

Tom : You never wanted to be anybody's girlfriend... and now you're somebody's wife.

Summer : Surprised me too.

Tom : I don't think I'll ever understand that. I mean, it doesn't make sense.

Summer : It just happened.

Tom : Right, but that's what I don't understand. What just happened?

Summer : I just - I just woke up one day, and I knew.

Tom : Knew what?

Summer : What I was never sure of with you.