My girlfriend plays League...every night...until 5-6 A.M.

So my girlfriend plays League, which was totally cool, I play too, and we tend to have a good time, but while I will play until maybe 2-3, and every other night, she'll play until the sun comes up some nights, and she plays every single night. It's gotten so bad that she misses her classes, work, I never see her anymore and we live together! I don't know, it makes me pretty sad, just left on the side lines like this. I'm trying to wait it out...but I don't know...