[HelloKitty22]

You should definately not tell your sisters about your "plan." It would terrifying and horrible for them and would put a terrible strain on your whole house. That it is information which should only be shared with your doctor.
I think it is fine to want to share the fact that you have depression with a few close sisters. They may be able to speak to the chapter for you if you're having a hard time or serve as somewhat of an early warning system if you begin to withdraw and show signs of a deep depression. However, you have to recognize that sisters are not a replacement for a doctor or medication. What you have is a serious medical problem not a breakup with a boyfriend. You can not expect to go to a sister with your issue each time you have a problem or feel depressed. Your sisters aren't equipped to handle that. It can put a real strain on that sister (she's still dealing with all the stresses of college too) and on your whole house too. Concentrate on finding a good doctor who will help you to find medications that you can tolerate and who will help you recognize that you have a lifelong disease which needs to be treated. People who have heart disease don't stop taking their heart medicine. What you have is just as serious and will never be cured. However, what you have can be managed with medication and a good doctor.