just got a call from my mom my great grandma Is not gonna make it thru the night.. she has alzimers…

just got a call from my mom my great grandma Is not gonna make it thru the night.. she has alzimers /demintia and can't hold on anymore. she got put on oxygen yesterday and is not awake anymore she's gone mentally just waiting for the physical part.. don't know how I'm supposed to deal with this nobody I've ever known has died..