Have talked about this before sometime ago, but a specific Pok?mon OST pulled me right out my relapse and prevented it from going any further at 12. It was the most soothing thing I've ever heard and it was and is still able to calm me immediately upon hearing it. It even cured a lot of my headaches and jaw pain in the years following, a feat nothing else was able to accomplish for me. Not for the agonizing pain I had in those years. I owe a lot to that OST for, quite literally, being the most stabilizing factor in my life to this date. I'd have been way worse off without. Nowadays I listen to it in virtually any circumstance, but especially when I'm anxious or sad.
Other music still affects me, too. I especially get solemn/sad due to music, more than happy. Only times I get really happy is when I listen to metal, because the aggression in that music is so exhilarating, that kind of rush is just great. Music also helps me focus on studies, but I'd really need to find a song that fits my mood if I want to listen to it while studying. I seem to have a thing for more complex music arrangements so I naturally lean towards VGC (mainly, but not limited to, Pok?mon).