He definitely is being immature and disrespecting your interests, but how is he otherwise? If he is like this in other ways, maybe you are upset because this is a symptom of a bigger underlying issue in the relationship. If he is otherwise respectful and loving, I say to just brush it off...take value in what you are and who you are becoming and don't worry about the naysayers...spirituality is intensly personal...maybe he had a bad experience with it growing up or has even confused it with religion. My boyfriend is intensely anti-religious (he grew up in a Muslim country)...I'm not religious either but would call myself somewhat spiritual. When he makes fun of my yoga classes or calls me Polyanna when I try to see the positive side of things, I just laugh inside and feel a bit sorry for him...He's otherwise a good guy and this rarely comes up, so I don't find it all that important....Besides, I make fun of him for playing video games and watching soccer....and it doesn't bother him at all.