It sounds like you need a break - don't beat yourself up about it.
We all reach the end of our limits. I've told my son before that if he hated living at home so bad we'd have to find a place for him to go. I've also been at the point in traffic that the thought would cross my mind for a few seconds that I should drive straight into a semi.
You might feel differently later, or maybe you simply can't go on with things the way they are - and that's OK. Maybe that will even mean she'll eventually get the help she needs if you're not there to pick up the pieces.
My son has been on two involuntary holds, and while he was very, very ill, he was much better behaved during it all than your daughter. Here, if she saw the same people my son saw, I don't think there would have been a problem.
However, here, they have something in the law in addition to immediate harm to self or others. He can also be incapable of taking care of himself or protecting himself from harm. For example, if you go out and sit in the middle of the street and won't move even if there's traffic, you can be completely quiet, but it could show that you're not competent to protect yourself from harm.
That's how they did the holds on my son - he had not threatened anyone else, he was not being abusive to anyone, he was not threatening to harm himself in any way. But, it was obvious he wasn't eating or sleeping, he could barely get a single thought out, and we was so out of it that the first time they thought he was overdosing on drugs.
For now, you just do what you have to do to keep your own sanity. You never know what the future holds.