Wow, this sounds similar to (but definitely worse then) my situation. I would definitely say that confronting her is a good thing to do. I live with 3 other women, 2 of which are older than me. Meaning I'm 21, and the others are 20, 27, and 36. The 36-year-old is the one we're having problems with! I've always been very nonconfrontational, and telling off someone who's 15 years older than you is really hard to do, but I finally did it. She's done things like eat everyone's food, drink everyone's alcohol... stuff like that. And she's the biggest hypocrite ever because she THOUGHT someone ate one of her nutrigrain bars and she flew off the handle! I had half a bottle of expensive wine left and it mysteriously disappeared. I found it, empty, in her room. I also had a full large bottle of Bacardi Limon, and she drank the whole thing during the course of a weekend. Her idea of replacing it was to give me a bottle of $5 champagne
Since I never see her, I wrote her a short note about it, and she apologized. I'm hoping it never happens again. I'm going to have to confront her AGAIN because she left about 20 dirty glasses on the kitchen counter, and they've been there for 2 days now. It wouldn't bother me as much if she hadn't written a 3-page letter to one of my other roommates for leaving ONE dish in the sink for ONE day. And she's also been kinda weird to this same roommate... See, normal roommate answered the phone one night and it was for weirdo roommate. So normal roommate takes the phone down to weirdo's living area and knocks on the outer door (weirdo has the whole basement to herself). There's no answer so normal roommate slowly goes in, then knocks on weirdo's bedroom door. Weirdo says, "Come in" so normal roommate goes in. There's weirdo with her psycho man she keeps sleeping with off and on, and they are both naked without any blankets or anything on them! Apparently weirdo wanted normal roommate to join them!
Anyway... I always feel that a person can't be expected to change if you never tell them what's wrong. I've been known to let a lot of stuff slide, because usually it's no big deal and usually doesn't happen very often. But some things ARE a big deal (such as everything your roommate has done) and some things happen way too often. It's at these times a confrontation is necessary. Who knows, maybe she'll be so embarrassed that she'll move out
