Friendship is dissolving bc she hates my boyfriend...?

She's obviously got some deep emotional issues and is very insecure. All you can do is have a heart to heart conversation with her (when she's sober) and ask her why she hates your BF. Pin her down and make her be specific as to what he does to make her dislike him. Ask her how exactly is your BF brainwashing you and what are his motives for doing so. Also, ask her why she thinks she is behaving the way she is. Why did she get drunk and puke in your car? Why is she rude and mean? Ask her why she thinks it's OK to be rude and mean. Have this conversation in a matter of fact manner. Don't get angry and remain calm no matter how she answers the questions. Avoid defending your BF, getting into an argument and attacking her. Just let her talk and just listen. Your goal is to get her to talk about the way she feels and hopefully in the process she'll realize on her own that she doesn't have very good excuses for her behavior. Keep your expectations low, because she's not likely to change her attitude or admit she's been wrong, but you never know.