i noticed this difference very profoundly when i moved from florida to massachusetts, in the wintertime the days are soooo much shorter up north.
i don't live in mass anymore, but in general i deal with it by:
making sure i get up early even if i don't have to
getting outside 20 minutes daily (during daylight hours) (that's a goal, not what i actually do, but i push myself if i'm feeling down)
switching on all the lights in my apartment as soon as i get up so i am looking into bright lights
these habits do seem to help.
i also moved west, where there are more sunny days even during winter compared to new england, for this very reason.
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161 Aspie / 51 NT - Aspie Quiz (very likely an aspie)
36 - AS Quotient
115 aloof, 123 rigid, 89 prag - Aut/BAP
24 - HSP / ADD Quiz- 41, Inattention: 24, Hyperactive/Impulsive: 17
"Odd and different is beautiful" -- Tyra Banks