AskDrFeeder:
I've heard this story many times. A person has no interest in feedism but is persuaded to try it by their feeder. They gain some and by their partner's reaction realize how erotic feedism can be. It starts to turn them on, and before you know it they appreciate gaining on its own merits. They'll want to continue even if they break up with their partner.
Has this happened to you? Can you add any details? (I've heard of this happening many times but no one seems to be able to describe it very well. )
Why feedees and not feedists?
I digress.
Can't teach someone to participate in a kink they don't want to participate in. And if they do, there's no guarantee they'll participate in it the way you want them to.
All you can do it kink negotiations. Maybe they'll be into it. Maybe they won't maybe they will decide they prefer to be feeders, mutual gainers, or fat admires than feedees.
Open, honest communication is sexy. It can be a little scary, but you owe it to yourself and your partner to try.