Hello maddnessreturns: To be honest, I don't know.

The bottom line, from my perspective, is one cannot expect anything.

You simply get what you get.
My personal experience has been that people who don't struggle with mental health issues don't want to know anything about it & will avoid becoming involved with it to the greatest extent possible. As a result, it falls to those of us who do struggle with mental health issues to find a way to not push family members & friends, etc. beyond their tolerance level. And if we cannot, or will not, do that then we risk losing them because they won't put up with it forever. Some won't even put up with it for very long.
I don't know how long you & your S.O. have been together. If he's asking you "how often you get like this"

perhaps not that long. Unfortunately this may be a harbinger of things to come & something you're going to need to consider as you contemplate your future with this person.
I'm sorry to be so negative about this. But again from my perspective... we're pretty-much just on our own. It's a large part of why many of us are here on PC.