Donna, buy yourself (or steal one from your office's stationery cabinet ) a little notebook, and every time you do something new, different, get positive feedback from a customer, or improve a process, write yourself a note about your accomplishment with the date.

Firstly, when they are playing mind games with you, you can sit with your glass of wine and look through your note book and see the difference you make to the company, and all the good things you do. It might also be useful at review time, but hopefully you can find a better job soon and won't need a next review time there

I remember a job, where the only criticism of me was that I sometimes laughed a little loudly. OK, whatever ...