How can I relearn how to play?

Everything you listed stimulates your brain only…I would suggest you get up and go out and do things that stimulate your body and mind. A simple walk in the woods will do way more for you than playing online games. Humans interact with other humans in person…give that a try.

Put up a swing of your own in your backyard if you have one. I would also do has @Cruiser suggested and find something to stimulate your body like a walk, bike ride, going for a swim, even go for a sled ride down a hill.

This isn’t actually as expensive as you would think it would be. You can get buckets of Knex on eBay for pretty cheap.

Either volunteer to walk dogs at the local shelter or adopt one that really likes you and take it to animal parks and on hikes and let it love you. You will become creative and happy. I have no T.V. I get all I need on line except for exercise which my four footed furry faithful friend takes care of with walks and TALKS.with her or with others. I live in a small apartment and have a dog who likes people, dogs, squirrels,bunnies.and cool to cold wet weather..So we are outdoors in the northern Puget Sound area with weather , conducive to the “blues”.if one stays inside. Grey skies will boost serotonin even with clouds blanketing the sky.

Yes you CAN swing on swings. I go to my local park and do it and I love it. I also climb on the jungle gyms. There is no rule that only kids can play there. I just make sure that none of them are waiting for whatever I am using.

Try something more hobby-like; like painting, drawing, some kind of craft… or music, maybe? Get a recorder and teach yourself to play… Do you have open space where you are? You could buy a kite and fly it.

I never got the memo that adults can’t swing. I do it every time I’m at the park.

Take regular walks to the park. Perhaps there is one tree you pass, maybe at the entrance, maybe farther in. Notice that tree every time you pass by. Are the birds all the same birds each time? Do their songs sound different? Are there squirrels, or any other critters thereabout? Get to know that tree as a community of animals. Then look at a closely neighboring tree. Do the same animals use that one as well?

Check it out. A walk through the park does not need to be boring.