I'm sorry to hear about your daughter's struggles. It's very difficult to watch someone you love so much, go through hard times. From my own experience though, I would do EVERYTHING I could to avoid putting her on ANY kind of benzodiazapine drug - the drugs they commonly use for anxiety - even if she didn't have an issue with her liver, which I know is a major issue, and potentially life threatening situation when drugs are thrown into the mix.
I would keep exploring ANY type of non-invasive treatment, ie: counseling, group therapies, peer support groups, etc., rather than put her on any type of drugs. Anti-anxiety medications are only good for very SHORT term use, 2-4 weeks MAX, and after that they become very addictive and are a living nightmare/hell to get off of. Please research VERY carefully ANY drug that may be prescribed for her. To find out the truth about anti-anxiety medications and how horribly dangerous they are go to: www.benzo.org. In most people's opinions, NONE of the anti-anxiety drugs are SAFE for ANYONE, with or without other health issues.
Finding out the underlying cause of her anxiety and depression may take longer, and might be harder than just popping a pill....but if it were my daughter I would try anything I could, WITHOUT using drugs, to help her resolve the issues that are causing her to feel the way she does.
I hope this helps you some. If only to stress the terrible, terrible long-term effects that even small doses of anti-anxiety drugs have on a persons health and life. I wish you the best, and I hope with all my heart that you are able to find a way to help your daughter and keep her free from drugs, which will only create a whole new nightmare in her life within a very short period of time.
May God bless you and your family.