Families & Friends Of Addicts Support Group
Addiction affects more than just the individual. This community is dedicated to the families and friends of individuals suffering from any form of addiction. Mental health professionals are increasingly considering alcoholism and addiction as diseases that flourish in and are enabled by family systems. Family members react to the addicted person with particular behavioral...

I would write down exactly how you feel and send it to her...it might save her life...and in addition....make you feel better...
I'm sorry about your Grandad....Grandads..and Grandmas are so special...don't let this "cousin" trouble you .....HE is most important right now :(
Sorry to hear about your Granddad.
also, this is not YOUR problem. it isn't even your aunt's. It is only hers. and loving them or getting mad at them doesn't change much...BUT you might be just the thing that reaches her.
my son said the letter from his sister reached him...and they don't even talk. (for years while he was a drunk, and even now, 6 years later, they only visit if they have to at one family occasion a year!)
So....take care of you.