General

It's normal to only be turned on when your fetish is involved, thats the difference between it being a preference and a fetish I think.
I thought I was asexual for a long time before I discovered feederism and ive talked to a lot of people who felt the same.
I cant comment on that other bit because I have no idea what it is but isnt it normal to not be sexually attracted to people if they dont share your fetish ?

If you can be aroused when thinking about feeding someone, then you are not asexual. Romantic feelings are a separate issue. It us quite possible to fall in love with someone and even to experience elements of physical attraction, without arousal. Finding someone with whom you can experience romance as well as great sex can be difficult as a feeder or feeder. Happy hunting!