Has she ever been able to settle herself to sleep without being on the breast?
If not, the problem may be nothing to do with hunger or thirst, and everything to do with being unable to self settle and therefore over tiredness and ovber stimulation.
Self settling is an essential skill that has to be learned at some point - and the later, the harder, IME.
I breast fed my three for well over a year each, but there comes a point when you have to take a step back and consider your own needs, your lack of sleep and your mental health, and above all the quality of life of your family. As you have said you are too tired and ratty to do anything during the day.
I know lots of people will disagree with me, but maybe the time has come to stop breast feeding, and help your dd to learn to fall asleep unaided. You will all be happier in the long run.
I would really recommend "My Child won't sleep" by Jo Douglas and Naomie Richman. It explains far better than i can.
There is another quite recent thread about a similar problem, and I think it took less than a week to sort out. Maybe someone will remember and link. I am hopeless at anything technical.
I feel so sorry for you - I went through this with DS1 and the little book saved my life.