I totally understand OP. After my 12yo DD initial diagnosis, I did spend some time crying and mourning the "loss of my completely perfect DD". I guess I felt like I was at a crossroads, I could continue to spend energy to mourn or come out fighting aka keep experimenting at things until we found something that DD loved to do. After LOTS and LOTS of trial and error we found that art, swimming, and horseback riding brought her the most joy. It was just magical how she connected to horses. FYI, there are many therapeutic horseback riding orgs in the area (if your in MoCo) that have therapeutic riding (e.g.,
https://www.cloverleafequinecenter.org/). But if riding is too much, then just try to do simple things like finding the most colorful leaf at a park, feed ducks at a local pond, collect pinecones, make leaf angels.
I can't force my DD to do things that NT kids her age might like b/c it just sets us up for failure. I too have to meet her where she is and what she's capable of and actually listen to her. This was not an overnight thing, and it does take time.
A while ago, I think I saw the movie "far from the tree" on Amazon Prime and it just totally opened up my eyes.
https://www.imdb.com/title/tt6848736/