How to Rediscover the Joy of Programming?

Learn a programming language that changes the way you think.

Here are a few to consider:

Clojure - combines many profound ideas into an elegant whole that is well-designed and fun to use.

Rust - combines the speed and power of C++ with a more functional design and clever compile-time checks, giving a powerful language that is a joy to use. Rust is to programming languages what Vim is to text editing. It will take you some effort to learn and practice to master, but once you internalize it, you will never look back.

I wouldn't. Instead pursue other interests and if one day you feel like programming again so be it. You can't force yourself to be interested in something, you'll just end up miserable trying.

Do you program for a living? If you do, perhaps you should change jobs and look for new challenges.

Why have you lost it?