Re:
This statment: "we know nuts will kill him but we will never stop having nuts around him"
And this: My response would be " I can't stay with people who don't care about risking my child's life".
I think there is a non-sequiter here.
The OP has not been able to say that just being around nuts will kill her DS.
The family are saying that they appreciate that eating nuts will kill the OP's DS but they clearly do not believe that having nuts in the same house as him will kill him
Therefore to call them "people who don't care about risking her child's life" is not true, and the thread title is frankly hysterical or worse. They are people who do not believe that the risk to the OP's DS is as severe as she claims. That is not the same thing as knowing the risk and not caring about it.
I would love everyone to be milk, egg and nut free around my DS. But it doesn't happen, it's never even considered, except with nuts for some reason.
Would people be happy to come on holiday with me and be told they cannot have any dairy products at all for the duration? Even though my child, though reacting if he touched them, would have to eat some to have his life threatened? Thought not.
For all the years I have been coping with my DS's allergies, I have: taken his food everywhere, removed any other food/drink out of his reach and watched him like a hawk in anyone else's house. He soon learned not to eat anything unless we had given it to him, well before the age of 4, and he was not an advanced child at all.
As parents of a child with a life-threatening food allergy we have learned that it is up to us to keep our child safe, and to try to rely on anyone else is foolhardy. No-one else loves them like you do, no one else worries like you do. No-one else will check ingredients as carefully as you will. It's the way it is . It's upsetting that other people in the family aren't as careful, but they'll care a lot more than the rest of the big wide world that the child enters when he starts school. You can expect a LOT of blank looks and shrugs.
You need to decide whether an environment is safe for your child. I decide I don't want my DS to go to see calves being bottle fed milk on a farm visit - as there is lots of splashing and slobbering. The OP can decide to keep her DS away from her parents, and I probably would have done myself when my DS was that age.
But it is not a nut-free world and the anaphylaxis campaign no longer recommends nut-free policies (eg in schools) so there will be more of this to come.
I understand the OP's fear as I have lived it. But statements such as "my in laws are literally trying to kill my son" make me feel nauseous.