((((((( manda )))))))))))
Sweety, I'm sorry about what your little sis is doing and how you found out. But hon...listen to me....whether it's attention seeking behavior or whether it's real feelings she is having and going through, it is not and I repeat NOT your fault.
She has a mind of her own. She will do what she wants, just as you do. It's also very possible that she does feel depressed just like you do.
cantstopcrying is right...this could be a good time for the two of you to get together in a loving way and have a good heart to heart talk.
Wishing you both well.

sabby