Hi IDM

The fact that your boss hasn't shown you any value, does not mean that you don't have any value...........it just means that he's "not a good employer" for not offering an employee support when they need it/ask for it, and he's prepared to risk a task not being done for lack of a simple explanation to you when you asked for it. And btw.........kudos for building up the courage to ask!!!!
So.............it says everything about him, and nothing about you

Plus..........a job, income, goes no where near in defining your personal worth, you matter so much more than any of that IDM, which I'm guessing your wife knows too

But the task...........well you can only do your best, whatever that is in the situation.........and hey..........you managed to work up the courage to talk to your boss (!!!!!), I reckon you could ask one of your colleagues for some advice on this, right??? Certainly can't be as hard as asking your boss, right??

And maybe it would be an idea, to start looking for another job, even if for no other reason than you deserve to be treated better than you have been............for now though please try not to allow all of that to effect how you feel, and how you feel about yourself.
I know that may be really hard but but it/he honestly is not worth it

Alison