As a guy who is the one who puts up with the mood swings: We do it with great empathy, therefore we understand what is going on and that it isn't your fault. This also, however, causes us great pain.
All of this proves my "even number of therapists" theory, in which there must always be an even number of therapists in the world, with the garden-variety ones hearing out standard people problems and then the true gods of therapy giving the therapists therapy. The gods would give normal people therapy, but even they can't withstand that much without therapy, so they rely on sketchy memory and partial confidentiality from the normal therapists to "delete" some of the problems from the mix.
I just wrote a f***ing paragraph.