I’m in a similar situation as yours. I work somewhat between 0 to 20 hours a week. I am not rich but have enough to get by and don’t strife for more.

One important thing is: try to not see boredom as an enemy. It’s a luxury. Sometimes I lay in hammock just looking around, doing nothing.

More important is: have hobbies. I know it’s easy said and I have barely hobbies myself. But on those days I do my hobbies, those are usually real good days. If you have no idea where to start, maybe just workout a little. Not too much, as it’ll kill any motivation later. Don’t try to enjoy it but try to embrace the bitterness.

Most important is: have social contact. I know it might be one of the most difficult things in life to find friends or people you care about. I have very few friends, all of them living in another country, so we meet maybe once in 5 years. But I have a partner and kids. But those few relationships are the most important thing in my life. If you have no place to start, try the internet. I found the letter app “slowly” nice to get to learn people. Take it slow, take time. Alternative, you can try local “hobby” places, like the gym, some sport thing, groups where people repair things, …, whatever you have the slightest interest. Don’t say “it won’t work”. Give it at least one shot before saying so.

I hope I could help! Good luck!