I have been to a neurologists in the past multiple times and completed multiple courses of medicine. But those medicines I took had really bad side effects. And I realised the more I used them the more I was dependent on them for a normal mood. Also my brain felt foggy while working when I took them.
I do take time off after a few days of working but that alone does not help. This is a cycle. Planning on going out daily and exercising, eating more healthy and having a schedule with less screen time. Let us see how it goes. These things seem trivial, but I have never them for more than a month continuously. I want to give them a try this time like my life depends on it.
Writting about myself and what seems to have helped me.
Have been on medications for two years (getting off of them now), and in therapy for a year. Likewise, I had (or have) troubles with feeling stagnated/unmotivated after bursts of productivity and motivation.
The key insight was that creativity and productivity does not come without cost. I used to overwork myself and my body. After "feeding" the intellectual part of me, the other parts became "hungry".
The solution for me is to have breaks, even when I am in the state of flow while doing something productive, and use that energy to work on the dull activities that are required to keep me healthy - physically and psychologically. The stream of consciousness style of journaling helps me as well - it helps the root cause of my bad feelings show themselves, sometimes in a subtle way.
What you may want to have a look at is Active Imagination[1], it comes from Jungian analytical psychology. I find it really helpful.
Good luck!
A well put metaphore I've heard is that you got a set of forks which you use daily. Make sure you don't run out of them. The problem is that it feels so great just using them all when you get a new clean batch after a couple of days of downtime..
Good for you that you are aiming for stability. Setting a structure and planning for mentally tough parts of the day (like social events) and never parting from that can make a total difference in life quality. It would for anyone obviously, but with living on some spectrum it's a life ingredient. Yeah, it's tough, and yes your life (as in with great life quality) depends on it.