Need to find the name of this horror/comedy B movie

Well, when I was a kid I saw this really crappy movie. I was so young then, but this movie triggered me so bad I can remember most of it except for the plot. I suppose it is a late 90's/first decade of the 00's kind of movie.  In here, a teenager's skin suddenly starts shedding off. I am not sure why, but I think it involved her getting into a car accident or such, but she doesn't die as expected, and instead gets more and more disfigured as the time goes by. I remember her going home and then she starts getting a lot worse, like losing the skin on her leg and breaking her ankle, but she doesn't even flinch. I also remember her going to the kitchen with her bloody leg behind, just dragging it and then having a break in there as if everything was completely normal. I also remember a guy, and I guess that the way that they interact makes it a really creepy dark comedy instead of horror per se, because the behavior of the girl it's too "provocative" for her condition. Then at the end she ends up turning into a pool of flesh and blood, and that is all. Creepy, isn't it? Maybe some parts of this aren't close to what really was happening, but remember I was too little to understand any of it and I could get the wrong image or idea. Maybe it wasn't a full movie, but a fragment, a little short story inside a movie, or a series. But I am interested in finding this sick thing, you know, dusting out the skeleton's closet and such. I saw it three or four times on TV before disappearing completely. If you have any idea, please let me know. I already found Thanatomorphose, but that movie is not what I am looking for. Ah, the girl had brown to dark hair and was supposed to be very young. I think she had a skirt, but I am not sure. Hope it can help somehow.