I went thru that, without external support over 10 years ago -- basically my ability to concentrate and enjoy work vanished... It took me a year to 'recover' -- I don't think I was ever 100% of what I was before TBH, but it's because it helped me realise that there isn't JUST work that matters. I am a lot more pragmatic about work these days, and I no longer 'live to work' as I did before.

I don't know if any of these suggestions will help, but perhaps you should pick up a hobby, something that is not too taxing and is still rewarding. It can but doesn't have to be tech related either. For me it was Photography, and I do a lot of landscape photography to this day -- but it could be anything, perhaps these days I would pick Archery (field archery is a super way to 'zen' out).

The idea is to get back the feeling of doing something you enjoy, and it doesn't requires weeks of setup or zillions of hours of practice to enjoy yourself.

If your company is cool with it, perhaps negotiate a 4 day week, and take that one day for yourself to really unwind. Don't stare at the TV tho, so the thing you enjoy, and go out and do it.

But ultimately, what I suggest is that in the future you watch over your work/life balance. Take care of yourself!