Don't give up on this one. I really think she'd understand if you were to just explain to her why it wasn't a great night from your point of view. If she is a reasonable person, she'll understand. If not, then fine - she wasn't worth it anyway was she!

We all have nights where we just don't feel like we're hitting the right notes. And we have other ones where we hit them all 100% crystal clear and can't put a foot wrong. Learn to tumble with them both, and keep bouncing back for more.