Are my family members being rude and overtsepping the line?

[lux s]

Long story but my Moms sister is a very mean, controlling woman, she beat up her sons when they were little, vacums her walls, that type of person. She always bullied my Mom, my Mom stood up to her and for the first time did not attend Christmas at her house, instead she took a europe vacation with me and my sisters, Moms sister was furious, had her son write a letter telling off my Mother. hes 50 yrs old btw.
Then his wife left a message telling my Mom off because she didnt call back her husband right away and said "never call us again"..

After that Moms sister never called or her 3 sons (my moms nephews)....

The only people who call are two wives of her two sons(my cousins wives)....

They call 1 hour apart from each other at holidays never mentioning the cut off and make believe everything is normal. Then ask what all of us are doing and invite us over when my Moms sister will be there, knowing we were cut off.
Anyone feel its none of thier business? are they sirring trouble?
Are they fishing for gossip? I'm not related to these women, i feel they have alot of nerve calling. My Mom didn't call them back last time and one of them called 15 times, an hour later the other one called 5 times..
also my Moms friend died, her sister never notified us, and 2 months after she died, my cousins wife calls to tell us and then tells my Mom that she thinks her husband was cheating on her and she took it to the grave,
first of all its not true, My mom was really offended since this was her friend for 40 years and my cousins wife met her once.
I don't think their trying to put an end to the fighting they never mentioned one word about it. And they ask alot of questions like what street am i working on, what hotel are we staying at on vacation, where are we going on our next vacation, etc.. they also never call for birthdays, etc