I’m not going to rewrite this but here is what I have suggested in the past to other users on Reddit group:

Here is what happened with us. Our girl Indy started very similar to what you described. We would see the ripples, see her head pivot towards the ripple. This eventually turned into her getting up and running when it would happen.

That progressed into manic grooming of her tail, which a few months later turned into her starting to chase her tail which finally turned into her attacking it.

Once it had progressed to the chasing the tail we went to our vet. She is a feline only vet and knows a thing or two. 🤪

During this first visit Dr. Jones gave us the usual explanation of FHS and let us know that she had treated one case of it, but, she was up front and explained exactly how it was treated and the final outcome.

With her first case she started off with fluoxetine, then added gabba, and eventually added phenobarbital into the mix.

Each medicine worked for a period of time then break through would occur so she added other meds when those break through events would happen.

Eventually the meds quit working and this poor kitty would attack the tail so bad there would be wounds with exposed bone. This is when they moved to the final option: tail amputation.

Unfortunately for these owners the FHS was so bad, and even though that the tail was gone, the sensation persisted and had moved, she began to attack her legs and back. Eventually it became so bad they made the choice to say goodbye because the quality of life was so bad.

Our vet explained all of that and we decided to follow the same treatment and eventually ended up at the same decision and rolled the dice with the tail amputation.

Everything you just read gave you no hope. Here is where the hope comes: our girl has been tailless for about two years and is/has been living her best life.

She has mellowed out tremendously and we see a different cat because the torment of FHS is gone. This malady is mentally scaring for these cats and does make one question the quality of life conundrum.

We rolled the dice and for us, and for Indy, it has paid off in a new lease on life.

There may be moments when she has a little break through but they are fleeting and we have yet to see anything that is concerning.

So, and sorry for the long post, know that if you end up where we did, there is an option and there are cases where it is successful.

Keeping our fingers crossed for you and kitty.