Extended family gatherings can be a communications minefield where you never know what—including the truth—is going to set someone off. I can sympathize but I can’t solve all your problems in one short blog post.
I can, however, recommend Claudette Chenevert’s 31 Days To Better Communication (available on Amazon.com–no affiliate link here). You can put these “best practice” tips into action and see changes in yourself, in your family, and in the emotional atmosphere of your home and extended family gatherings.
What are you waiting for? Wouldn’t you like to be one big happy family by the time the next holiday rolls around?