She's a stupid f***ing b**ch for going on a trampoline -- those things are death traps! Her dad probably made you the "bad cop" for chickening out on putting his life and health at risk.

Speaking from experience, does she like you in general? cuz when I was 13 my dad had a gf (now his wife unfortunately) and I didn't like her, and I probably would've said the same thing because guess what? thirteen year olds really aren't that mature generally!

You're okay dating a guy who raised his kid to behave that way? Did he at least do anything about it?

Delightful child and so well brought up too.

You don't. But she may be perceiving that he spends more fun time with others besides her. I think you're doing fine, and I'm sure you already talked about this with the bf

With the information I have received from your post, I suggest not continuing this relationship. It's not going to get better.