How to handle an abusive boss.

I have worked for the same company for 9 years and worked my way up, improving my position. My manager has always made me uncomfortable because she is outspoken and critical of everyone and speaks poorly of employees, the owner and other executives in the company and anyone else she takes issue with. I have managed ok despite my discomfort until last year. A year ago I made a couple of pretty big mistakes in my work. I am not making any excuses but at the time was experiencing some personal problems which did not help. I was mortified by the errors and did my best to correct everything and yet still turned around immediately after that and screwed up a different task. My year was not great personally and in turn my distraction did not help my work. This portion is being added to say I have deserved for her to be disappointed, upset etc with me at times. I am willing to admit, I have not been a perfect employee. We have had some talks in which I was honest and of course apologetic. As the year continued on, I could feel more and more disapproval with both my work and personally. She brings up my past errors periodically which just confirms she has no faith in me. She was unhappy with the timeline for a project I am working on, she was unhappy that I was taking a lot of time off at the end of the year, among other things. Today was my first day back and immediately I felt disapproval about things we already discussed last month. Then this afternoon she came to me and basically said I lied about doing something because when she had someone look into it while I was out and was told I never did what I said. I do not lie and said so. I said lies always find you out and I would never do that. I did what I said I did - but when I went on the necessary website, could not find a record of my work. I was freaking out and said I know you will not believe me but I did exactly what I said. I told her all the steps I took in detail but she clearly does not believe me. To make matters worse, she said some very upsetting things about me to a co-worker which were very personal. I cannot afford to quit without something else lined up. On top of that, I am behind on some things which I am putting in extra time this entire month to catch up on. It is sad, because I do like my co-workers but the situation is untenable. I have zero self-esteem left, I doubt even the most basic parts of my job, and have actually wondered if I was losing my mind, for example when I swear I did something that is not there now. I already know I need a different position somewhere else. My question is, how do I deal with the situation (her) until I can get out? I have so little belief in myself, I feel like I won't get a position that pays what I currently make and do not feel equipped... which makes me feel more and more trapped. For the record, other employees have had similar issues in the past and see what is happening to me but nothing can be done.