I love Franz bread, having tried many varieties of gf alternatives over the years. It's still soft enough to make into a sandwich if you want, but still does best when toasted.
I love Pamela's pancake mix, and generally buy the Bob's gf oatmeal (most oatmeal is cross-contaminated with wheat do to the machines used to process it and the fields where it grows so you have to buy oats that are specifically tested.) If you want a fast oatmeal for breakfast and don't want to make your own (I'll make a double batch most days and leave it in the fridge and either heat it up or fry it up like a pancake the next day) Chex makes a tasty, uber-sweet oatmeal line that's gf.
I used to be a pasta fiend before going gf (I also have celiac disease, was diagnosed three years ago) and have found that I like the taste and texture of corn-based pastas best (Mrs. Leepers is a good brand) but many people swear by Tinkyada. Instead of pasta though I've shifted more towards rice and potatoes. You can absolutely put marinara/meat sauce on rice and it's pretty fantastic and alfredo sauce on roasted potatoes is amazing!
Glutino makes a great Oreo cookie alternative and like others have mentioned, Cheetos (original flavor, I'm not sure about the spicy varieties) are also gf (aka: they're made with corn and chemicals and probably crack, not much else ;3)
It's also extremely important to set up your kitchen to avoid cross-contamination! Is the rest of the family going gf? If not, then she'll need a few kitchen utensils of her own: a new cutting board, a strainer/collander, and a toaster. You won't be able to use wooden spoons to stir sauces for her because the wood can trap gluten proteins from previous uses. If you have nonstick pans, you may need to get a new one if the bottoms are scraped from previous uses (can also trap food.)
Yes, this is going to be a pain in the ass. Yes there may be tears (heck, I was 30 when diagnosed and I cried for about a month afterwards because I'm a carb-addict.) But this can also be an adventure! I've tried so many new foods since going gf that my dad is convinced that I've been replaced with space aliens! I was super picky before my diagnoses, but I've realized that in order to change my point of view, I needed to focus on things that I CAN eat instead of what I can't. It's definitely helped with my outlook on life.
Yes, there are times that I wish I could just randomly walk into a restaurant and order anything off the menu without worrying about cross-contamination and GI upsets. I always carry a LARA or KIND bar in my purse for times like this and then I can order a soda when I go out with friends. It does make me a cheap date ;) Pizza is going to suck if she likes thick crust, but "Against the Grain" is a delicious brand that I found at Whole Foods out here in the PNW. You can also make bagel pizzas out of Udi's bagels (found in the freezer section, pretty darn good.) I'd also recommend experimenting with making your own crust and trying out the different mixes that exist :)
http://glutenfreegirl.com/new-to-gluten-free/
The above link is a great starting point and she has a huge variety of recipes on her blog. Yes, some of them are complicated, in an unnecessary way, but I wanted to point her out because she just developed a flour blend that I like even better than Cup4cup! It's only available online (I joined the Kickstarter project) and it makes really "fluffy" baked goods :D It's also super easy because you don't have to worry about measuring out all sorts of starches and different flour blends (I tried this when I first went gf and it was much more trouble than I thought it was worth.)
Definitely feel free to PM me if you have additional questions or even just want someone to commiserate with :)