Welcome to psychcentral. Sorry to hear you're down. That you are trying physically to be active but can't really get into it, sure sounds like depression.. and you need either psychotherapy or medication to change things back to normal.Catch it early and it won't take so long to "fix".
I personally don't appreciate anyone who uses "just" casually.. as it sounds minimizing! Hormones out of balance can kill us or cause us to !!!! They are very important and help run the body. There are natural alternatives to drugs for hormone imbalance, and if there's chance that's a big part of it, then try it! Blue or black cohosh, evening primrose oil etc...

I understand the high IQ.... it can be a handicapp at times, and can make us our own worse enemy in trying find logic in illogical happenings. sigh