Dude. If you don't want to see her again then don't call her back. I can't even count how many girls I went out with once then never called back. I've only had one true grenade who I met online and I made it thru dinner then faked like I was tired and peaced the fuck out of there.

It's not like you can call her and say "Hi I had a good time with you but you're kinda fat so I don't really want to go out with you any more." There's no good way to have that conversation.