To be fair, it can sometimes be annoying being partnered up with a vegetarian. My husband is, but can't really elucidate why, other than he's really stubborn and never gives up on something when he starts it.
But I have had the holidays in Paris walking past all the wonderful restaurants and going back to the hotel for instant noodles because there's nothing vegetarian on the menus of any of them. Or never being able to eat out in France, Spain, Greece for the same reason. And I have been embarrassed by having to hand over a long list of requirements to relatives.
And eating at friends is always such a disappointment as they always default to vegetarian so it's either pasta and fucking pesto or some goats cheese monstrosity. And I hear from other people what good cooks they are and how their duck is to die for. But I never get to try it because he's vegetarian they view me as vegetarian too by default.
And it took a lot of the pleasure out of cooking for me. There was no joy in cooking a meal for one and having nobody to share with. So I just started cooking vegetarian, but it wasn't the same.
I suppose what I'm trying to say is that as the partner of a vegetarian you do have to make sacrifices for their principles. So occasionally partners might get a bit frustrated and snippy.
I know I do sometimes, and DH will tell me that he appreciates the fact I have made those sacrifices and miss out on stuff because of his principles. From my point of view it's a two way flow - he sacrifices stuff to be with a vegetarian, so a little tolerance for occasional frustration with it should come from your side too.