I have to echo the others. You may be an adult child, but this is still your parents' divorce, and it has NOTHING to do with you. Don't let this derail you from your goals in life. You can easily get sidetracked by trying to parent your Mom and your Dad because you feel you have to support them in addition to replacing them as parents for the other kids. I am not saying you should be totally selfish. Just keep loving them both and letting them love you, and don't be anything to your siblings other than the good elder sister that you have been. Good luck. My heart aches for you.