Perhaps you went back to work too soon, or ELSE your job is just too stressful. It's either one or the other.
have you thought about changing jobs? Of course the job market stinks right now, and finding another job could be really difficult right now. But your mental health is more important than what kind of job you have.
Whatever you decide, I wish you the very best. Take care of YOURSELF, okay? God bless you! Hugs, Lee