I think you are making your PIL out to be really evil, when all they have done is tell you honestly that they can't cope with hosting you over Christmas.
Because, maybe they can't?????
You say your children are rowdy, and their cousins are meek and mild, and give the excuse that it is because they are boys - which is actually totally irrelevant.
So you have rowdy children that you make excuses for.....that could be enough, just on its own.
you also don't like them, and have chosen PA gifts - this is weird, why spend money being PA?
so the have a DIL who they know doesn't like them, who was planning on arriving and being PA, who has rowdy children she makes excuses for...........
really, they have honestly explained they cn't cope with you over Christmas, but would be happy to see you after woods.
That sounds fair enough to me. i really can't see anything there to take issue with.
My parents rarely coped with all of us and all our children together, and we came at different times, for many years my brother went for Christmas, and we went for new year, never occured to me to think anything of it at all, other than my parents were simply telling us what worked for them.
"broken"??????????
are you encouraging your dh to see this as something that should "break" him?
This is just such a non issue that I can't even explain enough what a non issue this is.