If you're not familiar with Office-Politics, Franke James' wonderful website, I'd recommend it highly. People write in (and have been writing in for almost 8 years) with their office politics dilemmas, and Franke or one of her group of advisors offer supportive and clarifying responses.
I'm honored to be part of Franke's advisor posse; this link is to a letter she had me answer a few weeks ago. I thought you might find it useful – it's focused on how to recover and create a new, more productive and positive work environment after leaving a politically toxic one.
Franke is also the author of Dear Office Politics: The Game Everyone Plays. It's fun + useful + realistic — one of my favorite combinations.