Whoever said that writing is an obsession, I agree with that. I am an obsessive writer. I work about eight hours a day, though ten to 15 hour days are not unknown around here. Most nights I can't sleep unless I spend some time writing beforehand. When it's going really well I can hear the voices of characters in my head, the smells and sounds all around them.
Nothing comes out perfect the first time for most writers.
It's hard work, but the piece gets better every time you go through it again. I'd do it again if I could, but there comes a point when you just have to let it go. Yes, I listen to music while I write. It's a habit I picked up in college or high school when I was pretending to do homework. I load it up and go to work.