Is there any possibility of discussing this with a psychologist (possibly through free Employee Assistance if your workplace has that) before taking it to your boss?

I think that might be helpful/result in better outcomes.

Reading this, I don't know if
a) you need a holiday

b) you need treatment for Anxiety/Depression

c) you need a part time job instead of a full time job

d) you need different duties

e) you need to work for a different organisation