Even when medicated, it takes a long time, and a ridiculous amount of mental effort to lock them in. They are also still fragile as spun glass.
As for the depression I know it. I had 2 types. Burnout was the most obvious. I'm actually on half the medication dose I was on. It turned out I had gone over the hump, and my mind was overloading. The kickback from that caused a depressive state. Backing off put me back on the peak.
The 2nd was wile coyote like. I managed to reduce the stress I was under, by a mix of medication, cognitive, and behavioural changes. Without the stress however, my emotional lockdowns released. The depression was environmental, but I couldn't even feel it, under the weight of stress. It was like wile coyote running off a cliff, all good until I stopped and looked. I'm still chipping away at it, but it still helps that I can feel it now. Before, it was still there and affecting me, but I wasn't aware of it.