If you practice musical improv your current emotions will come out in the music. If you are stressed or angry or sad, the music will reflect that, and then as you play and discover new melodies and rhythms and chord changes and themes the emotions will shift into something else, usually happier.

So you can use the language of music to more finely and deeply feel your emotions and work through them. You work them like you would work a muscle, musically.

The principle to notice here is that we can have creative bio-feedback with our emotions.

The same principle applies to using chi-kung to feel emotions in the body. You get creatively involved in the way you hold and feel your emotions in your body.