It's interesting that Sigmund Freud once wrote to the concerned mother of a gay son that nothing in his Psychoanalysis had the power to change sexual attractions. At least in that letter, Freud seemed to dismiss the possibility of conversion therapy or even the need for it. (Other communication from him on the subject is more ambiguous.)
But by a couple decades later, his daughter Anna, who had taken an important role in the Psychoanalysis movement, was pushing conversion therapy hard. She insisted it was morally necessary, very much unlike her father, and she insisted it could be effective.
Sadly, conversion therapy became entrenched as a desirable practice in the mental health community for most of the rest of the 20th century.
It took a long time for professionals to acknowledge what mountains of clinical data were showing them — that conversion therapy doesn't work and has profoundly negative mental health consequences.
Even today, with over a century of convincing clinical data at hand, far too many people deny reality.
Thanks for your story and your efforts to educate!