Yeah. It's difficult but fresh fruit, vegetables, meat, eggs, and dairy is the way to go IMO.
I bake my own bread or make arepas with masa harina. You can just mix masa with water for tortillas, tamales, arepas, gorditas, sopes, and waffles... with egg you can make pancakes and crepes. Maseca masa harina is at Walmart and most supermarkets in the US and it is gluten-free.
Then there are alternatives like gimbap and musubi and Vietnamese fresh rolls. Potatoes are a very nutrional carb and you can top them with stuff like pizza fixings or General Tso.
I got this book online from the library https://www.amazon.com/Sandwiches-Without-Bread-Low-Carb-Gluten-Free-ebook/dp/B077Q3LRJC
You can make gimbap and cling-wrap it unsliced. You can freeze musubi individually wrapped and let it defrost. You can wrap Vietnamese fresh rolls. Left over GF lasagna or pizza is good. I like cold spicy peanut butter noodles. You can pack GF sausage and cheese and rice cakes to assemble. You can make tuna-cucumber boats. You can bring baked tofu cutlets and dipping sauce. Coleslaw and potato salad are good. There is this book I got ate the library https://www.amazon.com/Sandwiches-Without-Bread-Low-Carb-Gluten-Free-ebook/dp/B077Q3LRJC
I get you on the rut.
Ideas for lunch: gimbap, onigirazu, musubi, japchea, cold spicy sesame noodles, cold meatloaf and mashed potatoes, cold lasagna. Salvadoran pupusas, cold tamales, potato salad, baked marinated tufu with dipping sauce, tuna salad in cucumber boats.
This book I got from library https://www.amazon.com/Sandwiches-Without-Bread-Low-Carb-Gluten-Free-ebook/dp/B077Q3LRJC
You could thin it down to use as a sauce on spirilized vegetable “noodles”.
I use this spiralizer after trying a few https://www.bedbathandbeyond.com/store/product/oxo-good-grips-reg-hand-held-spiralizer/1044825102
Even though I have used it for years I just tried raw soiralized English cucumber with vinaigrette for the first time.
Could also just have it on shredded cabbage or “cauliflower rice”.
Using it as a spread you might find ideas in this book that I was able to borrow online from my library https://www.amazon.com/Sandwiches-Without-Bread-Low-Carb-Gluten-Free-ebook/dp/B077Q3LRJC
Maybe edit out just that last sentence in your post :)
Gimbap.
My public library had this book https://www.amazon.com/Sandwiches-Without-Bread-Low-Carb-Gluten-Free-ebook/dp/B077Q3LRJC
I found this ebook at my local library https://www.amazon.com/Sandwiches-Without-Bread-Low-Carb-Gluten-Free-ebook/dp/B077Q3LRJC
This is my GF bread… takes about 5 minutes to make https://www.reddit.com/r/Celiac/comments/t3am1n/brown_bread/hys8xoy/
Another option is pupusas and arepas https://www.reddit.com/r/Celiac/comments/tk978r/psa_dont_forget_about_pupusas_recipe_in_comments/
Arepa video https://youtu.be/xdiUcPuZ7-A
But for low carb bread you want chaffles https://youtu.be/4MScRqhM6xk
I found this ebook at my local library https://www.amazon.com/Sandwiches-Without-Bread-Low-Carb-Gluten-Free-ebook/dp/B077Q3LRJC
This is my GF bread… takes about 5 minutes total https://www.reddit.com/r/Celiac/comments/t3am1n/brown_bread/hys8xoy/
Another option is arepas
I found this ebook at my local library https://www.amazon.com/Sandwiches-Without-Bread-Low-Carb-Gluten-Free-ebook/dp/B077Q3LRJC
I find good stuff at Asian markets. A Vietnamese shop near me in Canada has inexpensive GF labeled stuff from Asia, the Caribbean, Africa, Middle East, etc.
Explore Asian rice noodle dishes and Caribbean and Persian rice dishes. Try different rice varieties such as basmati and sticky calrose.
The Dash mini rice cooker ($20) is handy for one-pot meals and tye recipies work well GF https://youtu.be/q5wmmJoopPo
A big find for me was Maseca masa harina https://www.walmart.com/ip/MASECA-Traditional-Instant-Corn-Masa-Flour-4-Lb/10291185
Maseca is usually 4.4lbs/$3.40 and you can make pupusas, tamales, arepas, sopes, etc. With egg you can make pancakes, crepes, blintzes, waffles, cornbread, etc.
For pizza for example: 1/2 cup Maseca, 1/4 greek yogurt, teaspoon of oil, pinch of salt. Shape on parchment paper, top, bake in oven on the parchment paper at 425F for 12 minutes.
Then look up potato recipes: au gratin, scalloped, Hassleback, poutine, kugel, shepherd’s pie, etc You can serve reheated stew, curry, and Chinese food on smashed microwave potatoes for a quick lunch.
Try alternatives to sandwiches such as musubi, gimbap, onigirazu, or even cucumber tuna boats. I found this as an ebook from the library https://www.amazon.com/Sandwiches-Without-Bread-Low-Carb-Gluten-Free-ebook/dp/B077Q3LRJC
A simple solution for sandwiches is mini waffles (the Dash mini waffle maker is usually around $14) https://youtu.be/4MScRqhM6xk
A flour tortilla salad wrap with this salad https://cheerfulchoices.com/simple-fruit-nut-salad/
Check out Korean gimbap. Korean japchae. Vietnamese raw spring rolls. Szechwan cold spicy sesame noodles with julienned vegetables. Spam musubi and crudités. Baked falafel with yogurt dipping sauce. Tabouli salad. Pasta salad. Potato salad. Cheese and summer sausage on Scandinavian flatbread or dark German rye or French rusks spread with margarine. Calzones or Cornish pasties. Jamaican patty or curry roti. Italian tomato pie. Baked tofu slices with dipping sauce. Leftover lasagna or meatloaf are good cold. Different vinegar based coleslaws. Spiralized beets with cheese and walnuts and a balsamic vinegar and honey vinaigrette. Spiralized carrots with matchstick cut apples and blue cheese dressing. Waldorf salad, Cobb salad.
I was able to borrow this ebook from the public library https://www.amazon.com/Sandwiches-Without-Bread-Low-Carb-Gluten-Free-ebook/dp/B077Q3LRJC