Background: together 20 years, married 18, 3 kids. Both successful professionals etc. Everything fine. DH has a bit of a control-freaky personality but has never tried to control me, never been abusive or violent or anything. Bit lazy about domestic/kid things. Slightly sexist and homophobic but I pick him up on every single inappropriate comment or thought every time and he gets annoyed with me for being 'too PC'. I take being 'too PC' as a compliment 
Anyway, about a month ago, and I can't remember how we got to this, he said "you know how you would always think that in the end a woman enjoys being raped, because she can't help enjoying the penetration? Well I was thinking about it and I think if a man said this I would say, well imagine being raped yourself - would you really enjoy it?" So when I had picked my jaw up off the floor I just said "just in case it's unclear at all, women do not enjoy being rape victims."
Then I tried to forget about it, but I can't. Should I bring it up and discuss it? What can come out of that? Have I really been living for 20 years with someone who only just realised that women don't like being raped???!!!
I'm not sure what I'm asking but don't want to keep thinking about this by myself, nor tell anyone in rl. I realise the remark and the thought were both repellent. I'm not sure about the next step.