My mother became a vegetarian the day after Thanksgiving when she was 21. It is much easier to be a vegetarian today than it was even 15 years ago. Thanksgiving meals can be quickly prepared with meatless substitutes that taste as good as the real thing. (Obviously, this idea is subject to personal opinion. After all, I've tried meat and don't like the taste of it. I can palate soy meats much easier.)
Don't get nervous, I use a soybean based vegetarian alternative to regular chicken. It comes in large rolls from health food stores and is very versatile. We find many uses from slicing like lunch meat to dicing for enchiladas to shredding for chicken salad.