don't make it your passion but get interested...allow her to share her passion with you
for example
Cori's passion is shooting and firearms...not mine but he wanted to teach me to shoot (not my favorite idea) but I figured, why not? It allows us time to be together and he can share this passion with me I will never be a member of the NRA but I can learn to shoot I can take an interest enough to remember things he tells me so I can reference it later I can take mental notes so when a birthday or important event comes up, I am ready...I ask questions and am interested in his answers
you can't let the things she says rattle you (I know...easier said than done)
you have to remember that she isn't really sure so she has to try out a bunch of things until something fits just right but if you keep changing then she will never know how you fit
you have to be sure
then whatever she says won't change how you feel, how you fit you will be calm and steady and you will be the guiding force she needs to blow those changes against and will be able to guide those winds away