I totally hear ya. In fact, I switched teaching positions because of it (and a few other stresses). I am usually a learning resource center teacher for learning disabled students. I needed a break from everything it seems.
So I took the teacher consultant position when it opened. It has been a tremendous year of growth for me. I've learned a completely different aspect of teaching (and working with adults.)
I think it is important for teachers to reflect on where they are at in their careers and make a change if need be. Burn out is ridiculous for special ed. teachers as it is. Making sure we don't lose our passion is the number
one thing we can do for our students. Without our passion, we can't inspire anyone to learn.
My advice would be to have a cognitive conflict with this person --a tough discussion to address how to move forward together. She or he probably doesn't realize the affect they have. And their negativity can infect the whole
staff.