This is my observation on this topic. I know many young adults on the autism spectrum. Many of them will identify somewhere on the lgbtq spectrum. As they get older, they start to realize they are not. Kids with autism develop sexual attractions several years behind their peers. So, when all the other kids are starting to get interested in relationships with the opposite sex, they start to feel, or are told by peers, that they must be gay, bi, trans, etc. Since, they have less hangups with stigma, they just assume that is who they are and are fine with it. Then a few years later, they start to mature into their true sexuality and often decide maybe they are not what they thought.
I have just personally seen this happen a few times. I think I would probably let my kid work that out for themselves. But, of course, as with anything, keep them safe from abuse.

Regardless of the new label we can slap on someone, that person is still an individual. Your son is 17 and will soon be recognized as an adult free to make is his own choices some of which will be seen as mistakes in hindsight. The difference is your son has a diminished capacity emotionally and socially due to ASD. You need to listen but also offer solid advice on growing up and making his way through life. It's a lifelong task.

The LGBTQ group sounds hypocritical in wanting their group to be taken seriously while trashing special needs students. It's a pecking order in school and lots of kids don't want to be on the bottom of the pecking order. People feel more powerful in a group and will or say things they wouldn't have the guts to do on their own. Things sure have changed since I was in high school but I assume school staff are reluctant to be openly critical of any group that can give them grief politically speaking. Lastly, most people see high school as an experience that we learned from and moved on. Nobody will care who or what you were in high school as the real world will present new challenges. Will he go to college or get a job post high school?

"I refuse to join any club that would have me as a member." -Groucho Marx

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What is Gender Fluid?

Certified Sex Addition Therapist, Maybe your Pastor can recommend a Christian Advisor. Fast and Pray! 🙏🏽