[Sadrain]

We don't NEED music to regulate our feelings, but it does affect them and even us physically. Music therapy's effects are scientifically proven, as far as I know (but don't beat me, if I'm wrong).

Personally, music has always been my means to help myself. Depressed, desperate songs help me when I feel like that - I sing or hum along, maybe just read the lyrics, and my feelings go with them. Sometimes I'm stuck on the song for days or more.
When I feel better, hopeful, I usually listen to music that has inspirational theme.
I generally prefer lyrics over the song or music itself, but that is not the absolute rule. Pan pipe music, classical, just some instrumental pieces here and there have also helped me with my feelings. Very few times, it's rhythm and voice alone that captures my attention.
But, in the end, I listen to very broad spectrum of genres, artists and have wide collection of one or two random songs by random artists.
Music also is often my inspiration for writing, I find music I associate with character and listen to it and lyrics while I write the profile or replies and it spurs my fantasy. So, yeah, for me music and emotions are very closely related.