The exact quote is: "PENNY- (to Leonard) Why are you making such a big deal about this anyway."

I read this as her saying get over it.

If Leonard told Penny he accidently married someone, she would get out her wine bottle, get drunk at a bar and bed the first guy she liked. So why can't Leonard drop her off at the party and go look for Alex.

I'm just getting tired of Penny and the way she treats him. If she really loved him, she would be afraid to loose him and would be begging him to forgive her, telling him she would get it fixed immediately and please don't leave me.