It's not for you to decide or assume that the fuel isn't there. I am asking for suggestions on how one might go about introducing the idea. I am not forcing anyone, and if she decides it's not for her, I would leave it at that. You are quite literally saying that I shouldn't bother trying.Nobody's saying you can't get people interested or that you shouldn't bother trying. What people are saying is if the fuel isn't there, no amount of spark is going to light it. You can try and get them interested, and if they are, they'll start. If they're not, then continuing to push is going to push them further away from both martial arts and from you.
The only other option is to become a dictator of a small country and mandate that everyone takes martial arts. You might have some success doing that. Of course, then you'll be more likely to be dethroned if everyone knows martial arts.
"You can try and get them interested, and if they are, they'll start"
That's really great advice! Any suggestions or tips on how to go about doing that?