I don't know if I believe in angels or deamons but maybe she watching over you and even if it's not actually that maybe in ur subconscious u believe she is looking over you because you looked after her for so long. If she caused you comfort I wouldn't be upset about not dreaming about the others u obviously formed a closer bond with someone who completely relied on you it doesn't mean you didn't care about the other people In ur family. But anyway I am extremely sorry for your loss I know when I lost my grandma life has never been the same so I can't imagine your pain losing three important people In u life