((Teen Idle)),
That is why I think she may be suffering from PTSD. Her behavior and pushing everyone away is a symptom of PTSD. I understand "you are angry" hun, but how she is behaving is the PTSD talking. The person struggling "withdraws" and doesn't want to "love or care" about anyone or anything, there is too much pain and trauma and it isn't even on a conscious level where she can really change it like you want her to.
It really isn't her fault, her brain just could not handle the trauma of losing a child and it now just feels pain at any reminder of "loving and caring about a child". She doesn't mean to hurt you either, she is saying what she is saying because that what PTSD does to people.
She needs to work with a "trauma" specialist and you all need to meet with this PTSD/trauma specialist so the specialist can explain that she is experiencing something "profound" in her brain (not her fault) and "yes" she is a shadow of her old self.
I know this because I have been struggling with PTSD myself, I don't mean to be "less than I was" either and reminders of the trauma are very painful for me and I had very strong desires to just somehow not be here. My family was very "angry and even mean to me" for something I never imagined having happen in my brain, it's hard work and it takes time and patience to heal from. It is unfortunate that you and the rest of the family can't understand "why" she "just isn't stronger somehow", she doesn't mean it you know.
Children expect their parents to "just be so strong" and "know the answers and help the family recover from bad things". But parents are just people and they don't have all the answers and they "can" develop this reaction, but they don't mean to, and they don't do it on purpose either. Losing a child is a very "deep traumatic" thing for some mothers. In fact, Mary Todd Lincoln, never really recovered from losing one of her children, actually she lost all but one. I am pretty sure she suffered from PTSD, but back then they just thought she went kind of crazy.
I know you are trying to get her to see she still has you and your sister. PTSD is often just completely blinding and very unreasonable.
I truly hope she is working with a "trauma specialist", you all should be.
Here is a Link to read.....
http://carolkearns.com/columns/col_ptsd.html
((Caring hugs))
OE