You state that you are not enabled to the degree that your sister is...perhaps that is why you are better capable of sobriety. Perhaps that is why you are a stronger person.
You are the blessed one, because you are learning a better way to conduct yourself.
Remember, part of recovery is learning to take our own inventory.
Are you working an AA/NA program with a sponsor?
Maybe you can offer to go with your parents to an al-anon mtg.
Working hard to get out of the insanity of your parent's home sounds like the best thing
for your own recovery.