I am scheduled for December 19th, and while my mom has been very supportive, I have faced a little bit of questioning from my dad and husband. I bring this up because some of what your sister said sounds a bit like what I'm hearing from the men in my life. Chances are she is saying it, not because she doesn't want you to be healthy, but because she is afraid for you. As a fellow person who has struggled with clinical depression (and self-injury) as well as a few cases in my life where I have not followed through on something (y'know, if you ignore everything I have followed through with!), I was also frustrated at the seeming reluctance of people close to me. Your sister is probably concerned for your safety, your mental well-being, and perhaps selfishly how it will effect her when you are all together. I firmly believe she will get over it. But, you need to do what's right for you! Don't back out if this is what you want and need. She is probably dealing with her own fears and worries right now for you. I know that doesn't make it easier, but they love you! On that note, I am telling the rest of my family this week at Thanksgiving (two sisters know already...worried about the third and grandma) and my husband's mother (she will not be pleased, but again, I think it is more out of worry for how it could effect me and how it will effect her) in the next week or two. But, remember, you have everyone here as well!