I have Coeliac and maybe a bit of Fodmap. Apples and oats are out for me too.

The UK diet is incredibly focused on bread and wheat gets added to lots of things so buying snack food when you're out is really hard.  

Going to restaurants is a kind of Russian roulette nightmare for me, I guess through cross contamination. Going on holiday is incredibly stressful. I need somewhere self catering and I have spent whole weeks living on cheese and nuts. 

Chinese and Japanese food is sadly mostly impossible because although gluten free soy sauce ( Tamari)  exists and a lot of the food would be fine without the fucking soy sauce (!), coeliac hardly occurs in East Asian populations so the awareness isn't really there. There are a few restaurants in London that I haven't tried yet. If cooking your own, buy certified GF tamari as uncertified Tamari sometimes has gluten in. 

Italy has the most diagnosed Coeliacs in the world and eating out there is a dream because they are so distressed you can't eat pasta and bread that they really make sure your GF food is good. Restaurants are really on it, you can get lots of stuff in the supermarket. Rummo pasta tastes like normal pasta and there are a few other brands that are as good. Spain has a pretty good understanding of coeliac too. 

The worst is going to people's houses to eat because either they don't understand what gluten free is (' I made it vegan so you can eat it!') or they go to lots of effort and do it really well, but you get cross contaminated from their kitchen. Also you get gluten in things like malt vinegar, some Worcester sauce and other things that people add to a recipe without being aware. 

Basically, I take snacks about with me, I read ingredients labels and I have had to grow a tough  hide and learn to refuse food. And I still get sick several times a year from eating with friends.

I have a totally gluten free kitchen at home. The most important part of that is that it makes a big difference to the amount I worry about it. The biggest impact for me is not the actual eating, it's the stress and the organisation and feeling like I'm limiting other people's lives because we can't eat where they want or they've made an extra effort and then I've got sick anyway and then they feel bad. 

It's really nice that at home I don't have to have to constantly check that someone hasn't put breadcrumbs into the butter and jam or used my special non gluten-free cooking utensils or made pizza and thrown wheat flour all over the kitchen. 

As for my diet, it's really great. Most GF food tastes crap and often makes me ill for unexplained reasons, and I don't like the idea of xantham gum or pea protein or cellulose from wood pulp or all the other weird shit they put into GF packet food, so I cook almost everything. I never really ate packet food before, so the gluten free aisle is mostly a mystery to me but whenever I've tried it, I've often been disappointed. 

Of food in packets, all the supermarket gf brownies I've had are ok. I  like the Mrs Crimbles GF Madeleines and Deliciously Ella makes the best crackers for cheese, although they cost a bomb. Sainsbury's used to do a GF Lemon Madeira cake that tasted like real bought Madeira cake, but they've discontinued it as far as I can tell and replaced it with a much too sweet Lemon drizzle. GF corn flakes are normal cornflakes made in a different factory. Warburton's GF loaves are a bit cardboard but ok. The Coop chocolate digestives are ok, although they are oat so I can't eat them (probably for the best). Marks and Spencers GF cakes are fine.

Apart from the Rummo pasta, I eat food that is made with gf ingredients rather than subbing imitations and it turns out that is most food in the world. 

So for carbs I eat rice,  beans, chickpeas, lentils, buckwheat, quinoa, maize teff, amaranth, millet, cassava, tapioca, sorghum, tofu, chestnuts, potatoes and other root veg. Most of those can be eaten whole or ground to use as flour. I make cakes with nut flours. I make pancakes and flatbread, and most non UK cultures have traditional bread substitutes made of gluten free flour, like farinata and galettes and arepas or Vietnamese rice paper, which you can buy . Even the UK has potato pancakes. 

If you can eat almonds, they will become the staple of your baking. Polenta and almond cake is the most reliable cake to bake yourself. Tarta de Santiago is great. There are very nice Spanish almond biscuits called Almendrados that a child could make that are super quick.  Flourless chocolate cake is harder but worth mastering. Brownies aren't hard.

With UK food a lot of it is actually meat and veg and you can eat totally normally but you have to do is make sure noone is thickening the sauce with flour or coating it in flour to get a crunch or dumping in packet ingredients. When you start exploring the cuisines of the world you find lots of options to eat gluten free and my diet has improved in taste and nutrition. It's a nuisance, not a tragedy.