This is a totally off the wall suggestion, probably, but--
how far north are you?
My DD has typically struggled to be motivated/rational (emotionally-stable, even) between mid-November and about, er-- March-- of each year.
I didn't REALLY put this together until she was about 6-8yo, and not until she was 8-9 did we seriously consider the seasonal nature of her problems. Now, it's also true that the school calendar coincides toxically with this tendency anyway, so JUST as the shine of novelty is wearing off and the reality of drudgery/repetitiveness sets in, she slips into peak months of S.A.D.
You can probably see where that leads, right? Loads of existential angst, ennui, and placid (or not-so-placid, depending upon the day) refusal to do pretty much anything without prodding... feelings of worthlessness/ isolation/rejection... emphasis on the very worst aspects of her anxiety/perfectionism, avoidance and self-handicapping that cause a downwards spiral.
Just a thought. Maybe it's real and it's not just you being primed to see what isn't there.
In the two years since we took radical steps (lifestyle modifications) to address and control DD's S.A.D., she has undergone a remarkable transformation.
