I'd say your situation definitely falls under "special circumstances". He doesn't want to hear about sex PERIOD. It's not about him trying to pretend something isn't happening so he feels safer in his relationship. At least, that's the impression I got.
Hopefully sometime in the future he can find a way to work through his issues from the past so he can be more comfortable in his daily life, since sex is EVERYWHERE in our society.
Pan Female, Hinge in a V between my mono (straight) husband, Monochrome and my poly (pan) partner, ThatGuyInBlack