<human>: As the title says, I've been with my girlfriend for about a week. So far it's been pretty fun, although my sister won't stop complaining about me hanging out with my girlfriend, claiming I do it "too much."

Before I met my girlfriend, I used to hang out with my sister before school and at lunch, because I had no real friends at my school. My sister would occasionally let her friends (without asking me or telling me) hang out with us before school, and during lunch, my sister's friend and her sister would sit at our table, even though I don't really get along with them. This routine's been the same for around 2 years.

So last week, I asked my girlfriend out, since I'd known her for a long time and had strong feelings for her. She said yes, for some reason. So this last week or so, I've been hanging out with *her* instead of my sister, to which my sister gets mad.

But here's the thing: I don't think I'm in the wrong here. I mean, I'm hanging out with my *girlfriend*, something I *should* be doing, especially since I don't have a lot of spare time after school to hang out with her, since I work most days of the week. And it's not like I never see my sister outside of school; we live together and we work together at the same store. So I mean, it's not really a big deal IMO.

So what do you guys think? What should I do about this? I know this is a pretty boring story compared to others, but I'd really like some help.

Summarize the given text in a few sentences.
<bot>: Sister hates that I hang out with my girlfriend instead of her, even though I see her basically every hour of the day. What do?