Hi QT3,
It's theory of mind; just have to realize that not everyone sees, views, understands the world the same way you do. And even when you feel compelled to share your enthusiasm, it is unrealistic to hope for anything beyond someone supporting your excitement and realize they are no more interested in the topic than you might be in what someone's cousin wore to wedding (perhaps.)

The starting point would be to get into an organization and plan a post-grad path that will bring you in contact with people who share an enthusiasm in the same areas that you do. On the other hand, it is surreal to my mind the idea of feeling inadequate because people can't understand my interests. What matters that input compared to finding peers and in particular finding yourself a mentor who is interested in your interests?

When caught out by someone in your family, picture the tables turned with them sitting at a dinner with yourself and two or three of your favorite instructors.

I'm certain most of here have been there and have found or not found our paths through and beyond.