Well, nobody can diagnose your friend just by hearing about her, or diagnose her online. However, it might be beneficial for her to see a t who can work out why she doesn't take care of herself - even if she doesn't have a disorder. She'd have to see it as a problem first though, and she sounds very sensitive about the issue. Rather than being accusing, I'd try confronting her in a manner that voices concern. Let her know that you're aware of a lot of health problems which can come from not taking proper care of one's hygiene, and you're concerned for her physical health and state of mind. If you can tentatively and carefully mention the depression and how you hate the fact that she has to feel so sad sometimes, that might also help your point. Yeah, she will probably try to push you away, but hopefully you'll at least get her thinking in the right direction and let her know she has friends she can trust. If she really does have a true infection and won't take care of it, then it might even be necessary to inform someone. If that gets worse it could cause a major problems. Wish I could be more help in that area, but I'm actually not very well in the know about correct procedures in those cases.