My experience is limited, but we do try to limit gluten and wheat because my husband's family has a lot of food allergies. Plus, some people believe that wheat is not that good for us anyway and can cause problems for people who aren't really allergic to it.
How severe is the allergy? Is it just the gluten or is it any wheat? Does she have problems with other gluten grains? For instance, can she have spelt? I think you have to do a bit of experimenting to see what causes her problems.
I think there are a lot of gluten and/or wheat free products that your whole family can eat. Maybe not all the time, but in some cases. For example:
There are pastas made from other ingredients (e.g., rice) so you can make spaghetti that everyone could eat. Sometimes the textures are different and might take some getting use to.
There are baking mixes. I have made cupcakes that were actually good. I served them at my son's bday party without making any announcements about it and people liked them.
Your whole family can eat rice. Rice itself is gluten free, but some people think the enrichment process adds gluten. Here's an article about that
http://gfkitchen.server101.com/rice.htm
Luckily there is quite a bit of info about this disease out there. Invest in a good cookbook. www.mothering.com has some info.
Good luck.