Without an SSRI (or, with a mystical experience):
So, these are two potential experiences. In the first, the subject feels themselves in a downward acceleration, and then visits a psychiatrist, gets some pills, and levels off in a little sustainable valley.
In the second, the subject feels themselves in a downward acceleration, but stays present in that experience--even refusing institutional help if it's offered. The result is an intense downward speed followed by an eventual re-up-swing, and culminating in a wild leap back into the cycle.
And trust me, that wild leap feels at least as wild (indeed, as scary) as it looks here.