You can break free, and for your own good, you should, imo. The healthier you become, you'll realize how sick they are...and how they use you. Family dynamics are what keep you there...and feeling guilty for not doing everything! Once you are able to realize that they will use whomever is willing to be used, it might be easier to break away.
Perhaps you can find the agencies available to assist your family, in your absence, and leave that info on the table for them to contact .

You don't have to take care of everyone. It is your choice. Good wishes.