I could probably go for a diagnosis if I wanted to. I joined a waiting list years ago, and by the time they called I didn't care about having a diagnosis anymore. So I have not lived through this exact situation, but it seems to connect to situations where great expectations don't really deliver all that much, and/or are attached to a lot of boring work to do or details to attend to once the new reality sets in.

For example, after my first art exhibition I was very depressed because I realized this was not the feeling of happiness I really wanted to achieve. I grieved for this version of me.

And when I got to move into my dream house I was suddenly overwhelmed by all the stuff I had to fix and build. The idea of moving into the house was shiny and wonderful! Once I sat in the house I still loved the house and wanted to be there but I felt really weak and sick and unable to do anything for weeks.

Mostly, these days, I'm getting older and more unashamed. I don't even like the term autistic anymore - some old white guys made it up to repress weird people. I prefer the term neurodiverse, and I declaim that nothing is wrong with me. I am not disordered. I am proudly weird, and do mostly what I want. If you don't listen too much to what others say (psychiatrists and psychologists included) you will definitely get there! Your inner common sense will lead you to the eccentric life that is just yours.