I will pray for you, too, lamy.
I have to say that I really, really know what you're going through! I raised four daughters. One from age 7 up to her current 35 and the other three from birth to 21, 22 and 24 as of today. There have been many, many times in my life where I felt just like you.
And I love my daughters. All of them. I love them more than life itself, and I would do anything for them.
That said, they could also be extremely frustrating, irritating and difficult. And I'm not even talking about legal issues!
Looking back from where I am now, I don't know that I could or would have done anything differently. I was just doing the best I could at the time, and I feel sure that is what you're doing as well. Maybe she is too.
I would often pick up my youngster, carry her to her room. Tell her I love her but she had to stay in there now until I said she could come out. She could read, color, play or nap. But she could NOT come out. Sometimes it worked, sometimes it didn't.
Sometimes I would call on a babysitter to stay with them when they were terrible difficult. It was worth the 20 bucks to have four hours of peace and quiet - I usually went to a movie, ate popcorn and M&Ms.
The one thing I did not do enough of, but wish I had was stop whatever it was I was doing and simply sit in a chair with her on my lap until she calmed down or got through her negative/irritating/annoying moment.
Funny - that is what I wish people would have, could have, done for me. Still do sometimes.
You're doing fine. You're a wonderful mom! And feeling this way is an absolutely NORMAL part of being a wonderful mom.