Dear "fell in love,"
This problem sounds serious enough to seek professional help for. It certainly goes beyond the scope of on-line love life advice. You did, however, ask, so I guess I'll try to answer.
Two Types of Fetishes
There are at least two kinds of fetishes -- those that are harmless obsessions, and those that represent a real psychological problem. In either case, they are real "issues" for the person who has them.
Don't Abandon Him If You Love Him
If you love your husband, would you really want to leave him in a time of pain and struggle? I suggest that your husband needs a lot of help and support right now, not abandonment. On the other hand, being tough might mean threatening to really leave unless he takes responsibility.
You Might Be Only "Grossed Out"
If his problem is so severe that he could be a threat to other people, you need to get him help -- fast. My guess is, though, that it's really something you are more grossed out by than anything else.
Ultimatum: "Quit Or Lose Me"
I suggest that you give him an ultimatum: "either quit or lose me." He needs to know that his "harmless" obsession is driving you away. Sometimes behaviors that we "can't help" are there because we have never really received any negative consequences for that behavior. If he knows that you're being driven away by this, then maybe that will be enough of an incentive for him to stop.
You Can Help Him Change
What you wrote makes it seem like he really wants to change. I suggest that your loving support might make that really happen.