Have you actually educated her on the illness? Has she read any books or worthy websites? From reading your post I see three possible scenarios. Like I said, uneducated. Second, maybe just one of those people that will never understand mental illness no matter what you do or say. Third, she is saying these things out of fear? Like how she was making a comment about you being tired and not hanging out with friends. That's her way of saying I'm scared for my sister of her being alone. I don't know if I'm making any sense. If this is fear she doesn't really know how to talk to you about it. Is it possible that you two could do a therapy session together where it was in a controlled setting?

My sister and I have a long history together. She is almost five years younger than me. When I was 15 was when the BP came out, but I was misdiagnosed as having depression and was put on SSRI's for years that triggered me into a manic state. My poor sister witnessed so much that I will never be able to take back, and she also had her own demons to fight. I also had to deal with OCD as well growing up. There is stuff she tells me that I did and I don't even remember, I think I blacked out or blocked it out. Without my sister I don't think I would be here today. There is a bond that just cannot be broken between us.

Maybe deep down inside your sister is scared and wants to be there for you, I don't know, maybe it's worth a try to find out?