Having done a math PHD and now working as a programmer I find math proofs and programming semi-similar. Though I think programming is less "relaxing." In mathematics if you have an argument that works and isn't insanely complicated you can call yourself victorious. You can look for a simpler method if you want but there is really no imperative to do so. In programming there is almost always a better way to solve a given problem and the differences in speed matter alot.
High barrier to entry. I expect that at my current skill level I'd get caught pick-pocketing the first time I tried it, and that would impact my ability to try it a second time.
It seems like you just really like programming.
There's a seemingly limitless amount of skills that fit these criteria:
I disagree with the statement that electronics "is basically still programming". There are similarities between the two, but also significant differences; particularly if you consider electronics outside of the digital realm.
I also do not understand why you question whether math is "useful in the real world". I imagine that anyone involved in engineering, science, finance, artificial intelligence, marketing or a great many other "real world" occupations would vouch for the usefulness of mathematics.
Social skills. If you have no skills at all, simply going to omegle and chatting with strangers can be a first step.
If you want to get further you can focus on dating, coaching, negotiating or networking.
Studying stuff using spaced repetition systems, e.g. Duolingo. (Though it may lack "useful in the real world" depending on, among other things, what exactly you're learning.)
Music. It's pretty much all math. Every part of it. When you try to learn a riff, and you play it, and it sounds like you think it should, interesting things happen.
I have a mathematics PhD and have worked in academic research, industrial mathematics and software development. I agree with Princess_Stargirl that mathematics and programming feel quite similar, but for me mathematics is less relaxing because it's harder. Yes, it's great when you "have an argument that works and isn't insanely complicated", but until you get one you don't even know that it exists. Which is stressful if your pay, or reputation, or career prospects, happen to be governed by your success in finding such things.
(Whether, and how far, the same is true in programming depends on exactly how you define "programming". If you take it to mean the whole process of going from nothing at all to high-quality software, then it does share that characteristic with mathematics. But the very researchy open-ended work is a smaller fraction of programming than of mathematics, and there are people happily and productively employed as programmers who do scarcely any of it at all.)
Programming is quite a remarkable activity: