I'm sorry you feel this way. I work in PACU too and I love it. Sometimes we get overworked and stressed, but normally we rally together as a team and try to make the best of it. There are way more good days then bad, and my patients are rarely "awake enough" to truly be mean. My kids call me a ninja nurse, because most of my patients will never remember even seeing me or being in the PACU.
It sounds like there is a huge culture problem at your place of employment. I've been in nursing for 25 years and have seen a few individuals who can make work miserable, I stand up for myself. At first it makes things worse, but in the long run, it works. But most of my experiences have been positive, with teams that work together. I have found that my direct supervisor makes a big impact on the culture of the unit and how pleasant/awful it is to work there.
It would be ideal if you could find something different while you're going to school, if not, I hope you are able to see the light at the end of the tunnel. It would be horrible if everyone had to give up compassion to survive the workplace. I'm sorry this is happening to you and it's got you so down.