Hurrah - my mental health has just shot back up! I'm convinced that when you feel "of use" but not in danger that's when you're happiest.
I'm an IP lawyer and I've just used my 25 years' of experience to get a CD19 therapeutics deal between two companies rushed through. I was able to explain in 10 minutes why they needed to spell out A,B and C and why all the legalistic guff could then wait.
Also, I've waved from my balcony at my neighbour who lives alone on her balcony and listened a bit.
God I feel better now. It's so hard when the things you would usually do are counterproductive....