Had a very similar experience but did not handle it so well, so i lost a few days to it. It's like i was expecting the motivation to return by itself and drive me, instead of finding a way to move myself from this low state. I found there was much anger also with the underlying thought of self-defeat "it's beyond my control" in regards to the repeating cycle/pattern.

It's very cool to read this blog to see how one can handle this experience in detail through, first of all recognition of the pattern and then self-directed actions to change it into something that can be sustainable