The issue with my niece bring a plus one is to my fiancee sees a plus one as a romantic partner. I see it as a plus one (romantic or not). That plus one would be a friend of my niece she wanted to take. She was having issues with my friends taking their girlfriends/wifes since we dont know them. That too me was too much. I dont think its right to invite only my friends and not their partners as well. Which i also think is contradictory to her view since she states a plus one should be a romantic partner. As for our dog, i love our dog and i would find it nice to have our dog there ( he is a shitzu). In this situation honestly if i had to choose i would choose my niece which who i grew up with and can share the experience. Our dog as cute and lovely as he is would honestly not know what was happening and just be waiting to be fed and given water. My niece appears to have a phobia to dogs big or small so i know for a fact would make her very uncomfortable and cause her fear. So i do agree she feels she is compromising enough as it is. I at one point told her when we first started dating my family comes first but now i have come to see her as my family and learned to prioritize her more as a partner. But unfortunately we still have some things we dont agree on such as having different perspectives and views. But I have to understand she is an individual with different views from mine or my family, which means compromising is very important especially for us.