The Spring Depression: Skipped

Every spring, my Seasonal Affective Disorder comes sniffing around.  It’s an insidious thing I must be watchful for; the way I discovered it is that I said, “Hey, I seem to have had an annual suicide attempt in June for the past three years, this seems to be A Thing.”  And that timeframe got bumped up a bit when I moved to Alaska – theory was, all that excess daylight triggered something odd in my body – but the fact is, every spring, I’m going to have a solid ten days crying and trying hard to stop from cutting myself.
Except this year.  Why?
There’s three theories:
1)  The catastrophic trauma from my triple-bypass surgery stopped it dead in its tracks.  It sounds strange, but the other time I had major surgery for my burst appendix, it truncated what was a pretty nasty depressive incident.  Which is a strangely heartening thought, that even my body views this depression as a sort of luxury; if there’s something seriously life-threatening, it’ll stop making me sad and concentrate on getting me to live.
2)  I’m eating far better than I was before.  More fruits, more fish, less meat and sugar.  Could be.  I’ve been on some strange diets through various iterations of SAD, which never helped before, but I’m told by some that fish oil helps.
3)  Super mega-doses of Vitamin D.  My cardiologist put me on a weekly, prescription-level dosage of 50,000 units of Vitamin D.  Which, I’m told, helps ameliorate depression – something I’d shrugged off before, because a) I drink more milk than any non-calf being in the known universe, and b) I’d already been taking a vitamin supplement. But this is the theory I stick to – lots of other people find Vitamin D helpful, and so I’ve started taking a daily supplement just in case. (As Sheldon said, it might just be “the ingredients for some very expensive urine,” but the pills are comparatively cheap.)
None of this is to say that my SAD vanished. I had a couple of days where the slightest jolt would send me into sadness – a fight with a sweetie, a rejection, a writer who said something I felt was unfair – but it was at least a triggered depression, not the kind that just enfolds you out of nowhere.  And it was a 4 out of 10 on the Crushing Depression scale, something that might destroy a non-depressive, but my depression-fighting muscles are strong.
So I dunno.  My advice to you is if you suffer, try taking 5,000 units of Vitamin D daily, and maybe a pair of fish oil caplets at night.  (Always at night.  Otherwise, you risk getting the dreaded Fish Burps during the day, which is bizarrely traumatizing.)  I think the body chemistry is what’s causing it, but it was very nice to have glided over the SAD this year instead of falling in.
Or you could try having a heart attack, followed by a chest-cracking triple bypass.  Wouldn’t advise it as a strategy, but if you give it a go, lemme know how it works out.