Why am I so mad?

I was quite bothered this weekend I`m not sure why this particular episode bothered me so much, but here goes. My younger sister just got married last week Sunday night. My aunt from my father`s side took home videos of the wedding, mostly of our family(meaning not my mother`s side, or the choson`s side), She made a copy of the DVD for the Choson and kallah, who watched it, and gave it over to her older sister during sheva brochos to watch. I put in a request to get it next, everyone agreed, we decided that I would get it from them by Shabbos Sheva brochos. Well after Shabbos i ask the older sister for the DVD, and was told that it was given by her husband to my mother, i was so mad. I don`t know why, but it always bothered me, and still does bother me, whenever my mother takes something that belongs in my fathers side of the family, but he has no concept of how these divorced family's work(for the record he does come from a divorced home as well, but there everyone is still talking, and everything is all good, I don't think he knows about any of the garbage by his parents since he didn't care and was able to get spoiled by them, maybe its a good thing, but he has no idea how to keep things separate and that's what makes me more mad than anything). When I asked the Kallah to please get it the next time she is in the house, her response is I`ll try. Why is everyone so scared of my mother? Why does she come before everyone else?

I`m lost maybe others that have gone thru some of the same things can help shed some light as to why this bothers me so much.