I can imagine how scary this is for you.
It is sadly becoming a very common allergy so foods should be labeled well.
If this becomes severe (some people are so sensitive that walking into a room where peanut oil has been used affects them), there is a new method to ramp up antibodies and though it never fully removes the allergy, it makes it less reactive.
See your allergist and discuss it with him.
Though nuts tend not to be outgrown, don't discount it. I was allergic to strawberries and eggs as a kid and outgrew that.
Thoreau said, 'A man is rich in proportion to the things he can leave alone.'