Boy, I would not recommend meth for severe depression. Or not-so-severe depression. Not being all moral on you at all--but I'm fairly new to a daily habit, and prone to anguished anxiety and depression and all that. But with a lot of meth comes it's own weird dysphoria, not even with withdrawal, just on the down slope of a session. Vivid despair-type stuff.
As for motivation, I'm motivated to jerk off all the time, and that's about it. It's just not been one of those turn-your-life-around drugs. Not in a positive way. Did lose twenty pounds.
But everybody's downs are different. I could list a dozen other things to try that might help more than theobromine, but you've hopefully already looked in to all of that before going straight for methamphetamine. I mean, if you like stims, there's Ritalin-marketed-as-antidepressant: bupropion/Welbutrin. Pharmacologically they do the same thing. Stimulating with some well-being.
Speaking of which, [mention]LotsOfExperience[/mention] why isn't theobromine sold as a supplement? Besides being a stimulant, I mean, they could find a way to dilute it a bit, y'know, dark chocolate without the calories?