I'm having a visit with my girlfriend's family, but I'm going to leave early.
Would you rather leave early or stay longer?
I'd rather to leave early because her family annoys me. They are so boring when they are together. I can't stand them.
You should let people know when you have to leave early. That is the polite thing to do. You shouldn't just ditch your gf's family.
My girlfriend and I aren't even sharing a room, why should I care about staying longer?
You should leave if you want to leave, just make sure you let your girlfriend and her family know before you do. Even if the visit has annoyed you, you shouldn't be rude and leave without anyone knowing. Don't you think they'd worry?