I sympathize.
At least you're not afraid to talk about yoga and spirituality with your friends. I was a closet yogini until a few months ago because I didn't want to deal with the ribbing I was sure I would get. (I had to come out of the closet to advertise a retreat on Facebook. It turns out that the ribbing I feared never materialized.
) It sounds like your friends at least smile and nod politely.
But even so, when people want to discuss the topic of yoga and spirituality, they usually greet the topic with a great deal of enthusiasm. If your friends don't light up and start demanding to know all about it, or start talking about their own practice, I wouldn't recommend pushing the subject.
I'm in a situation where I don't talk about yoga (because my friends aren't into it) and my work doesn't make for good conversation, so I have to get a bit creative at gatherings. My husband is a crack amateur photographer. We pipe all his pictures to the Apple TV, and sometimes people get intrigued about this or that picture. A conversation sometimes starts about various places that people have visited, or about photography. We also talk about cooking or gardening or music or kids or museums or pets or their jobs or........ People generally like talking about themselves, so I just ask questions about what's going on in their lives, and they're more than happy to fill me in. I'm more than happy to hear it.
That wonderful exchange between friends is spiritual all by itself. The spirituality part is felt rather than discussed -- if that makes any sense.
Still, there are times when I would give ANYTHING to be in the same room with someone who knows about these practices and who loves yoga and who is willing to listen to me blab about whatever. I recommend looking for an AYP group in your area or going to a retreat for that purpose. Tank up at a group meditation, and then the urge to get your friends involved will lessen. If they're curious, they'll ask.
Anyway, that's my free advice. Worth every penny!
P.S. I should have mentioned... Even though I haven't yet met any of the people who participate in these forums in person, they've become dear friends. The forum can be a good outlet for you as well.
All the best!