Mari, strange coincidence, but I had posted a similar thread on the Lupus Foundation of America support group - depression or bipolar is a pretty common occurrence in lupus patients.
I switch on yellow electric bulbs on my bedside lamps if I nap in the afternoon. In the winter if there is strong sunlight I don't need to, but if I take a nap when it is a little dark outside I always have those lights on.
In the summer when the curtains need to be drawn against the heat, the lights are again on.
I figured out how important yellow light was to lift my mood when I had a bad episode of depression in '96. It was one of the many things I tried an d one of the few that I had any success with. The episode lasted months and for much of that time I never left the bed. Those lights were on 24/7.
I have never tried a light box, because simple bulbs helped and still do. With lupus I can not use fluorescent lights or CFLs anyway.
Ten years ago when we built our own house we made sure there was a lot of glass. I have a french window in my room that opens out to the balcony. There are a lot of large deciduous trees outside, so the visual experience from my room helps to keep me on an even keel.