Take some time off. The clarity you get from disengaging will be stunning (or so I'v seen). I generally think for X years of high stress it takes 1-2 months per year. So you'll need 1-2 years to recharge.

It might be difficult financially. I don't know your situation on how feasible that is. Perhaps you have family and other hard commitments. But I think in general people tend to overestimate the cost. Wind back your outgoings. Head somewhere cheap. Meditate, exercise, eat fresh food.