Aside from the milk issue, friends also ask how we cope with not being able to eat peanut butter or any tree nut butters. It's really not that hard -- Ainsley is not allergic to soy or sunflower seeds, and there are excellent substitutes made out of both.
-I.M. Healthy makes several varieties of soy nut butter (smooth, crunchy, honey, chocolate, etc.)
-SunGold Foods makes Sunbutter, which is made of ground sunflower seeds.
Both soy nut butter and sunbutter look almost identical to peanut butter. In my opinion, soy nut butter does not taste quite as good as peanut butter if eaten by itself, but tastes very similar in a jelly sandwich. To me, Sunbutter tastes at least as good as peanut butter -- it is quite yummy. Ainsley likes both. Unfortunately, I discovered that I have a slight allergy to Sunbutter (it makes my mouth itch), so I don't eat it anymore :(.
The only problem with either substitute is the cost -- both typically run more expensive than peanut butter. Recently, I was delighted to learn that my SuperTarget carries Sunbutter for $2.99 a jar, which is by far the best price I've found for it.