What a scary night that had to be for you both.
I know you want to protect your daughter but that is no longer your job. She is a grown woman and is responsible for her own life and choices whether good or bad.
I have found that many of our adult Difficult Child have some sort of "disorder", ADD, ADHD, Bipolar, Mental Illness, etc......
All of these disorders can be treated with therapy and or medication. It sounds very simple however our Difficult Child are often reluctant to seek help. Ultimately it is up to them, we cannot force them and that is the crossroad we find ourselves.
Here is a link to a very good article on detachment. It has some very practical and helpful information. Many print it out so they can read it over and over to really absorb what it offers.
http://www.conductdisorders.com/community/threads/article-on-detachment.53639/#axzz48dI6M2WX
I know the word detachment may sound scary, like you will have nothing to do with your daughter. I'll be honest, in some cases it is best to have no contact or interaction with an adult child. It is up to each parent to discern for themselves. I have had to completely cut my son off before as his toxicity towards me was not good for my mental or physical health. I now have very limited contact with him.
Boundaries are key component in detaching. We have to set clear boundaries with our Difficult Child. Boundaries protect us and them.
It's so easy as a parent to lose our own identity as we become so consumed with our difficult child's life but our lives matter too.
One of the best things I ever did was to take my own life back and to live it fully. It was hard in the beginning as I felt guilty but it does get easier and the guilt lessens. I also came to understand that much of the guilt I felt was reinforced by my son via his manipulative actions. When your adult child tells you something like "I'm going to starve to death unless you give me money and if you loved me you would" this is pure manipulation. They will pull at our heart strings and use our emotions against us.
Please read the article on detachment.
Hang in there.