I'm not sure if music heals anything for me.
Earlier, when I was young, I struggled expressing some emotions, feeling they were unacceptable, and so, must be not permitted. I sang the words of others, I acted the emotions of their songs. That was my safe way to be angry, sad, hurt, confused, not liking life, so much...
I have enjoyed Toni Childs, and Tori Amos, for some songs which helped e express some specific anger. Really good for that. They're not really the music I would prefer, but for the attitude, expression and power, I think they are great. Tori also has some very sad sounding songs, as does Joni Mitchell. Some feel so personal to me I'll cry when I try to sing them at certain times. I love that some people seem able to match up with my feelings so well. I have felt my feelings to be validated by people I don't even know, unlike my own family.
I can't sing as I once did. Plus I am better now at expressing my feelings more directly. I write, but not songs so far. (Love to do that!) I have painted, too.
Now, I have this glitchy app on my phone, 'Garage Band'. I use the piano. I haven't figured how to use all the editing features, but I don't care much, because I play it so inaccurately anyway. I do, however, find I tap into or open up some emotions. Or what I play 'accidently' fits my mood.
Whether or not this 'music' is 'healing' is not a question I think I need to answer. I don't think it is damaging me, and I enjoy the little noise I create, (no, not loud - I can't do this loud. I actually could sing loud, but, when doing other things I fear making noise.)