Believe it or not repetitive tasks can be quite relaxing and even restorative (in the meditative sense). A couple years ago I started practicing (disc golf) putting in my back yard to get better at the game. Many don't because its boring. And it was.. at first. Then it turned into something else. I started to crave the repetitiveness. Training myself to be patient, to not feel down if I missed a lot, etc. I started to get really good, and oddly that brought me far less joy than the simple art of practicing. Turns out its an ancient, well known phenomena. In your case, its associated with (presumably) a negative experience so probably a bit different. I just bet most people that play that game start to get that meditative experience without specifically seeking it out, but return regularly (and benefit!) despite that.