Notice "secretly". AKA it could be things such as premade items with non vegetarian ingredients like soup made with chicken fat or cooked dishes with non vegetarian ingredients like a chili. once you get in the beans, the sauce, the cheese, etc. whether or not the meat is a substitute or not can be hard to tell. As to the OP I wouldn't worry about it too much. Jewish law (which i wouldnt normally reference except for this case seeing as it has an ideological viewpoint that could be useful) doesn't believe in holding punishment over accidentally eating non-kosher food. most rabbis, especially orthodox, also urge you to turn the sin into a positive spiritual experience by making it a reminder that your spiritual life should be much more commonplace and not so taken for granted. So make it a reminder that you should remember why you're vegetarian and what it means to you. That all being said, flip off what i hope is now your ex boyfriend. Honestly if he views your commitments as that much of a joke, and is willing to taint your food as a joke, chances are he's not mature or trustworthy enough for you. The guy's obviously not ready for a relationship and how you made it two years with him is beyond me, but I'm sure that there are other events where that's been the root of the problem.