I am looking for a story where a guy had a girlfriend at school who had a roommate who she was rude to. I believe the roommate had red hair. The roommate did not want to get close to anyone because she had a degenerative condition or something like that. He and the roommate went on a ski trip or a lodge and the girlfriend stayed behind. The girlfriend finally came and screwed another guy for a day or so. I read the story recently so within the last three months or so. For the life I cannot find it. Thanks in advance.