My 61 year old mother is a severe type 2 diabetic on top of a long list of problems like broken hip and ankle, me and my father have been trying to help her for years, she won't take care of herself like checking sugar and taking insulin and just sleeps all day no matter what we try to do. It's like she doesn't care. We have tried tough love as well as understanding. I am at the point of depression and not caring anymore. If she doesn't care why should we. I love my mother but I need some insight from someone who has been through this.
I am so sorry for the loss of your sister. While your mother may be paralyzed by grief at this time, because of her diabetes, this could have terrible consequences for her physical health if her sugar levels are not stabilized soon. Please let us know how things are going.
If someone doesn't want to do something it's very difficult to get them to do it. At one point I even yelled at my mother, trying to shock her into reality. It didn't do any good. She gave up, she wanted to die, so she did.