I can cope with Autumn/Winter because I realised eventually that I can't stop the changing of the seasons, so I have to work around it much more.
I'm retired, and I make sure to get out of the house every single day (except when it's icy or lashing rain) to walk somewhere. I prefer my own company TBH since I can then go wherever I want to! Then when I get home I'm pleasantly tired and ready to turn on the lights and pull the curtains, to settle in for the night. I live alone also, and love it so don't think I'm ever lonely, I'm not!
Some daylight in Winter is so important for well being. As others have said I was like a mushroom when working during Winter, in the dark all the time apart from the artificial lights at work. That was grim, but it never bothered me much as I just took it as part of life at the time.
Nowadays, I'm lucky I suppose. I go away before the schools break up at Christmas and come back when they are back! Just a cheapie to Southern Spain, but OMG the daylight, the sunlight, and the longer days until 6pm (especially on Christmas Day) are just so uplifting. I see my family both before and after that, we are all happy for each of us to do our own thing. Christmas can be such a pain for many, so escape is a great option, although I know not everyone can do that.
Other than that, I find things that are good for me. Everyone's different so what works for one doesn't work for others. I live about 25 minutes from the coast, so make sure to get by the sea at least once a week. Bracing and uplifting even if it's cold and breezy. Things like that, a new cushion cover, adding something great to Netflix lists, reserving a great book on Borrow Box. The little things.
Hope you'll all be OK. It won't be long before the snowdrops and daffs appear once again.