In a bout of major depression, creativity is just lost. The feeling that I will never get it back was a main source feeding suicidal thinking. Luckily, I sought treatment, and an analyst told me that this is normal, that it's part of the illness, and that basically nobody can be creative while being clinically depressed (yes, I was in a clinic at that time). That helped, at least a little.
I'm fighting, and I'm slowly getting it back. But it's hard.
This is not "a sample set of one". There's a pattern here.