It's pretty simple, I get depressed. I have a friend that also gets depressed, very depressed, around the solstice. My friend spends winters in New Zealand to combat his depression.
Beyond being depressed, I get just plain tired and want to rest. This year I have needed my rest. I had a brush with death earlier this year caused by a stress related illness. If that was not enough, a very irritating bigoted relative decided I needed five days of elevated stress over Thanksgiving. The holiday irritations have always been there. My only refuge are my children and grand children and they have their pressures which is why we do a 'Family Decompress' in early January. The only rules are relax and enjoy each other.
Maybe I am being a tad harsh, but doesn't "No" mean 'no'? And, just because one is unable or too selfish to understand does not make it OK to be disrespectful.
As for reactions from others, I get two kinds. Respect for my personal space, and disrespect. I know that they are well meaning, but that does not excuse the disrespect.