I'm diagnosed with depression and anxiety. The depression -the Black Dog- is an old foe coming out of my far from pleasant childhood, kept at a distance for many years before being strengthened by a toxic work environment. The anxiety is more recent and has to do with my wife's frail health, my daughter being a single parent to one autistic and one diabetic child and getting harassed by a complete cockwomble of an ex-partner, and until recently by elderly and increasingly frail parents who depended on me for everything. I hate to say it, but now my parents are gone and the funeral done with, I actually feel better!
But what do you do? You get on with it! I had CBT and I use the techniques to this day. I have medication that holds off the worst effects of the depression, but I still have bad days and black moods. I got constructively dismissed (manipulated into resignation), because I was too forthright in pointing out that the project management system they were stupidly wedded to wasn't working, that their risk-management systems were cosmetic and that their performance management was corrupt. I suspect if I'd been less depressed I would have been able to shrug at it all. But depression, and fighting it, is what makes me so feisty and intolerant of stupidity and unfairness.
I begin to suspect that depresion and anxiety are my superpowers. It worked for Deadpool with cancer!