Well, you’re obviously not alone, but I’d say you’re part of a small minority. Personally, as long as their are no health or hygiene issues, I love both the scent and taste. As someone already said, perhaps you ran into a woman who had an unrecognized health issue. A healthy woman may smell sweet, or musky, or even spicy. But, a persistent fishy smell is a sign of excessive bacterial growth. I learned that way back in high school health class. I’ve never heard of it hurting a cunnilinguist, but it should be addressed. For that matter, even going down on a woman who has a yeast infection won’t hurt you, although it may be unpleasant, if it’s a severe infection. Of course, if it is, she probably won’t be in the mood, anyway. 
As for getting over it, it’s certainly possible, but why worry about it? As Irishgirl pointed out, there are women who won’t let you go down on them. And, if you fall in love, as opposed to lust, with a woman, chances are you’ll think she smells wonderful. If not, I guess you’ll just have to, umm, suck it up.
It’s also possible that the woman who turned you off to the act smelled “too familiar”. Recent studies have shown that families have distinctive scents that are passed on through the generations. They also showed that people are programmed to find this familial scent repulsive when combined with sexual feelings. Nature’s way of saying “don’t mess with your sister”. So, it’s possible the woman you mentioned smelled too much like a member of your family.
And, honesty is definitely the best policy, on this. Perhaps, if a woman offers to go down on you, that would be a good time to make clear that you’re not willing to reciprocate. Perhaps not. Timing of such things can be delicate. But, all you really need to say is, “I don’t enjoy it”. Most women would probably accept that, at least until the relationship is well established, assuming you’re meeting their needs in other ways.
