This is something that sort of happens to me, and I really don't get it.
Yes, I almost certainly experience SAD, generally from about late September through early January, the worst being October and November. (It improves once it starts snowing and I can go skiing.) My GID also tends to peak in the fall and winter. The weird thing is that at a finer scale day (say, one day to a week), they seem to be exactly anticorrelated: days when I'm really upbeat, the GID is more intense; when I'm really down, I just don't care about much at all, including gender.
I think it may be just a cultural effect; that depression and GID are anticorrelated for me in general, but that because of this culture and how I view it, I perceive societal restrictions around gender more intensely in the fall and winter, and less in the spring and summer. But I'm far from convinced of this explanation; when i think about it, I can't think of any reason I would see things that way. Perhaps, apart from depression, there's just something more introspective about fall and winter. Or, in your case, rainy days.
~Alyssa