I have a similar problem. If I push, push, push my boundaries, I end up not able to do much more than sit on the couch and read (my happy place) for days on end (not hours, days, sometimes weeks). Nothing happens around that if I get there. I have been evaluated for depression and BiPolar disorder because I once thought the fluctuating 'moods' were indicative of the cycling behavior, but a keen therapists recognized the extremely high level of anxiety I had. She explained that the body can only operate at that type of level for so long before it crashes or shuts down. (I have GOT to get that report).
I've not learned a perfect coping mechanism, but I've tried to restructure my life so that I'm not pushing my boundaries, but rather able to see them sitting calmly in the distance. If I approach them more than from a respectful distance, it becomes too easy to cross over them, and then I get burned out. My husband has finally learned what happens if I continue to pursue 'normal' when I have crossed my threshold, and he tends to back me off of whatever is consuming me. But the last two times it happened, I ended up in the ER with migraines (which is my fun reaction to stress overload). The last time sent me through 3 days of hearing, seeing, smelling and feeling everything to a very painful level.
I've learned to allow myself rest times built into my tasks if I know that I'll be doing something stressful. I'm new at this tactic though, so I'm learning slowly. So far, when I do it, it has been working.
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Aspie Quiz: 148 ND/50 NT
AQ: 41 (AQ-10: 9) EQ: 17 SQ: 31 FQ: 44 RAADS-R: 178
ASD Diagnosed 4/22/2016