How should I deal with my friend?

My friend is narcissistic and in her mid-20s. She is constantly obsessed with her looks, worrying if she's fat, concerned about her hair and skin, etc. She's a nice person, but only because she wants to be praised and likes the attention. (She is a major people pleaser.) She is also extremely anxious and nervous. I don't know what to do. She compares herself to everyone- she always has to fit in and do what everyone else is doing. She gets jealous and bitter when someone else has attention or achieves something that she hasn't. I don't know what to do anymore.