My little bro has Type 1, and our parents totally ate meat. He has actually managed to reduce his insulin use by adopting a vegan diet

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There are all kinds of wonderful things that work as vegetarian protein sources:
Soybeans & soybean products like tofu & tempeh
Seitan, (say-tahn), wheat gluten that is cooked to have a texture similar to meat;
TVP - textured vegetable protein, great for chili or even for mock-tuna or mock-chicken salads
Nutritional Yeast - I make a not-parmesan topping using Nutritional Yeast, ground walnuts, sea salt & parsley - good stuff
Nuts, seeds, beans, etc.
Vegetables
Pre-made veggie burgers, not-chicken and not-beef fajita-type strips, not-chicken nuggets, etc.
The important thing is to be patient with yourself and learn how to prepare things in a way that you like - it's all different from meat, and in my opinion, none of it really tastes like meat. But it's good in its own right, if you prepare it well.
The only supplements I use are a B-complex and a vegan DHA supplement (it's like fish oil, but instead of being squeezed from a fish, it's squeezed from the algae the oily fish eat). I'm not anemic or deficient in anything - I'm hypothyroid (hereditary) and I get my blood checked every three months - so I'd know if I were missing out on anything.
Here's a sample of a daily menu for me:
Breakfast: Steel cut oats with ground flaxseeds and berries with a little light coconut milk on top (and sometimes some agave nectar or maple syrup)
Lunch: Ginormous salad of baby greens, spinach, clover sprouts, chopped peppers, tomatoes, cucumbers, garbanzo beans, kidney beans, olives, slivered almonds and marinated tofu with balsamic vinagrette
Dinner: Vegetarian chili made with tempeh, black beans, sweet corn, fire-roasted tomatoes and Hatch chiles.
Snacks: Apple with 2tbsp almond butter, or any fruit + a handful of almonds, or a Larabar, or mixed nuts with dried fruit, a soy yogurt and frozen fruit smoothie, or something else that combines a little protein and fat with some sweet, delicious carbs.
Of course I don't eat that perfectly all the time. I do lots of vegan baking, too. There are tons of websites that have all kinds of good recipes. Some faves:
www.veganyumyum.com
www.theppk.com
www.fatfreevegan.com
www.vegandad.blogspot.com
I find that many people think being vegan must be very restrictive, but I find it to be very satisfying and fun. Good luck!