Completely bizarre nightmare

Does anyone know why some nights are filled with bizarre nightmares? I don't know if it has to do with stress, something goofy I ate before bed or hormonal shifts--whatever it is, I wish I could make it stop! Last night I had a dream about my husband's aunt (that I have met two times, once 20 years ago and then again this summer) and my nightmare was at the reading of her will. There were so many people there and I only knew a few. It turned into an entire warehouse of things we were supposed to walk through and claim if we wanted them. I am so creeped out right now! She is old, yes, but why on earth would I dream that she had died?! The nightmare went on and on-too long to list all the details here but it was one of those times where I was really really glad when I woke up. I think it might have something to do with the fact that I miss having my Mom here to talk to. Actually I don't have any older women in my life anymore and it makes me sad. (Not only because I miss them but because I am increasingly afraid that I am becoming the older woman!) I remember a conversation I had with my Mom when I was in highschool...I was talking about grandma--her mom, and she told me she still missed her everyday-not in a morose or morbid way, just the fact that she wasn't there any more. At the time I thought, yeah, that must be yukky but I went on my way and didn't really think about it. Now I know what she meant...there is just something missing. Every time I see a Mom and daughter shopping or having lunch I want to stroll over to them and remind them to keep enjoying each other because one day it will be too late. Yep--this has definitely turned into a morbid blog...didn't mean to do that--guess it was the freaked out nightmare that got me started on this twisted path today....I promise things will lighten up next time :)