I can relate.
I think what he is or is not aroused by is of little relevance here (for starters, if this was even a question of a turn-on at all which is arguable, the "depths" of what people are aroused by in a theoretical sense is quite the rabbit hole, amongst men and women alike, and in a huge proportion of cases woud be labelled "screwed up" upon brief examination, IYSWIM).
It's the fact that he not only ACTED upon it, but considered it sufficiently normal and unobjectionable as to BOAST about it presumably without fear of reprisal that is deeply, deeply repugnant and frightening. I need hardly tell you that he's a piece of dogshit, that goes without saying.
I'm so sorry that you're having to deal with this all over again. Having experienced consent-related (lack of) traumas on more than one occasion, I know how much easier it is said than done to immediately accept on an emotional level all the things well-meaning (and in some ways correct) people say that you must tell yourself. Particularly if it's not the first time it happened.
And I think another complicating factor is that there is still the idea of a template response. It's changed, it's more abstract than before, because after a certain amount of time wherein the status quo is people labouring the point that "people might expect you to feel X way, but it's OK to feel Y way", it's pretty easy to feel conflicted and embarrassed and freakish if you feel X (or another completely different) way after all.
Just know that you needn't. I've been on the "Why?"-bound train, and the track runs a big circle and has no terminal. Totally fine to stay on it a while, but you'll need to alight one day, and at some point you'll feel ready to.
This mind sound ridiculous and may not work the same way for you personally, but I found that a big turning point was when my dominant feeling (odd mixture of doubting my sanity and recollection, overwhelming righteous, humiliated rage and hazy depression) sort of got so big that it was ready to burst, and when it popped after a few prods, it devolved into what might be best described as derision so huge it almost devolved into wanting to laugh at them. That didn't come quickly, but the amount of weight it exerted when it did was so much tinier than what came before it, and it's still getting tinier in increments now.
You're doing really well. Keep at it, but don't be afraid to do badly every now and again if you're too tired not to.
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