No matter where you choose to go, you're not choosing between your parents but rather what will be most convenient for you personally. Sucky situation for all parties involved and easy for you to feel guilt in that situation, however there's no reason to. You can always keep in contact and visit the other parent whenever you feel like it. One day you'll move into your own flat eventually and it's not like your parents will hate you for that. Hang in there buddy, even if things feel shit and hopeless now they will get better and you'll only look back at it as something that made you stronger. My parents had a nasty divorce when I was 18 months. Didn't have to make the choice obviously, but that's life bro.