Your mom most surely means well, but also is frustrated and reacting in a negative way. What I'd recommend is just trying to get through the year until graduation as best you can. Try to tune out or physically leave when the yelling starts, and look to other friends or family members or other adults as the role models and support.

It sounds like a cop out and it doesn't necessarily make it better, but sometimes it's the best you can do temporarily. (I'm assuming it's general nagging and such, not abuse?) My relationship with my mom improved very, very much since going off to college/moving out. (I've been away from home for 5 years now and currently live across the ocean from her.) We each had our space and could appreciate each other more. I'm not guaranting anything, but most people find their relationships with their parents improve once they move out.

My mom still nags and can make me feel really crappy, but I've learned to deal with that better, like I realize she's just going to be the way she is.

A temporary fix?: I found that our communication was better when we were driving in the car and being away from home in general; it may not be a heartfelt discussion, but tagging along with her during errands or, say, bingo night provides neutral togetherness time. I find phone conversations go amazingly well, but this tends to work when you're not at home. What about writing her a letter with your feelings? It might also prove a more neutral way to communicate.