I agree it is a huge shame that some counsellors push clients to "remember" false instances of abuse, creating a witch hunt. That shouldn't, mustn't invalidate everybody's experience with them. My point was that it can be difficult not to conflate the actions of the abuser with those of the spouse.
I agree that sexual abuse victims must take responsibility for their sexuality. I agree that they need to stop seeing themselves as victims and embrace their own power. I also refused to let some jerk from the past be an evil force in our marriage ... however, it took me 25 years from the abuse ending to figure out how to accomplish that fully. (And that was without any social workers involved.) Once I dug deep into myself, the degree to which the abuse had impacted all areas of my life was mind-blowing. And, felt wonderful to overcome.
Who knows how much SSMGuy's wife has spoken about her sexual abuse. From his perspective, it was almost irrelevant. Perhaps it has impacted her more than she knows--it's impossible to say, because she's not dealing with her issues.
You ask, "why is it okay for her to let that ruin his sex life or hers?" I don't think it is okay. I also don't believe that one person can ruin someone else's life--both partners have to take responsibility for that. SSMG seems to be enabling his wife's status as the victim, so presumably there must be a gain for him in not pushing for any change for decades.
