Oh, I sometimes think that about myself then I remember it is all mood related!

For your friend, don't diagnose her. This can be off putting and scary for someone. Instead, try to encourage her to seek help and that you're concerned not judging. Let her know an earlier intervention generally leads to a better prognosis with any mental disorder but qualify it as if she has a problem at all. You may see it as very obvious but, she'll very likely feel the stigma attached to these type of words right away.