Can't speak for anyone else, but I'm trying to impose a bit of a routine.
Will skype video chat with friends and family at set times each week;
We'll designate one night as a hobby night (whatever it is, even if it's just doing a jigsaw!)
Then there are the general hobbies to keep going, and fortunately I like cooking, so trying to improvise will take me away from recipe books, and maybe learning a bit more about what type of ingredient works with what else!
Might also be worth writing down any achievement (however small) during the day, to look back on. If you're in a negative mindset you're in danger of writing nothing, but even making a cup of tea might be an achievement if you're really low.