Do whatever you can to make the job work for you. If you can find time to take breaks that help you make it though the day---do it. If talking to your coworkers at times helps you get pass an empty feeling during the day--do it. My goal of every work day it to make it through while getting a reasonable amount of work done.
Try not to let yourself feel the "fear" that manger is spreading. That type of talk comes from insecure managers that think intimidation gets results. Nobody's work is perfect. It is healthier to get work done with the best you can do. That is all you can do.
I hope the replacement manager is someone really good.
No problem with venting....we need to vent to talk back to our depression.