J.W.
My dd was allergic to dairy until she was 1. I lost 70 lbs because of my "new" diet. LOL.
I just read labels - my little was was sensitive to whey and casein. I still served dairy items to my hubby, but I didn't put the sour cream on my taco, and my salad dressings were vinegarettes with no cheese in them.
I made (and still do) a lot of "whole foods" with nothing processed - grilled or baked chicken, pork chops, roasts, burgers, fish... You can still pan fry without flour, but we grill year round. Lots of veggies and rice. Mac and cheese is out, but until the allergic one knows the difference, the older kids can still have it (if you're not opposed to cooking 2 meals).
Use toppings like salsa to mix flavors up a bit. There are some canned gravies that have milk but some that don't. You can still do chicken, shrimp, tuna salads - just learn what breads you can have (or serve in a halved out tomato).
For dessert, there is a yummy sorbet at Safeway that is dairy free (Safeway brand). I loved the chocolate, but there are a few other flavors too.
Eating out can be rough as many restaurants add butter for a flavor enhancer. Just ask and explain about the allergy and they are usually happy to oblige.
Good luck! It was really hard at first, but got easier. BTW, LOVE your profile!