Dealing with Workplace Stress

Hi HN, I work in a busy, fast changing environment. I'm in a pretty senior role there reporting directly to the CEO. I have always had more work than my team could possibly complete, and coped ok with that. What is getting me stressed is the toxic culture from the top. My boss spends his day setting unrealistic ecpectations, blaming me for every setback, refusing to listen to logic or reason. I'm now off sick with serious stress symptoms. I want to stop feeling sorry for myself and get better. Apart from resigning I feel like learning to not care so much might help. Can anyone share any resources that helped them combat work place stress, and particularly any that helped them care less about the hurtful things said to them?