Me and my sister are going out for new years but I think I'm gonna ditch her at some point.
What did she do that would make you ditch her like that?
She moved into my apartment and just uses all my things without asking. It really pisses me off.
Being upset that she doesn't ask to use your stuff is fine and perfectly normal but ditching her for it isn't cool. You should have just not made plans if you were going to do that. It's super rude to just go out with her and abandon her there.
I'm gonna use her and ditch her like everyone I know does.
Its dangerous to leave someone alone at the bar on a busy day like that and very rude. You should tell her what she is doing to upset you but don't do that to her.