I can sometimes be overwhelmed by an emotion, even loneliness. I think I know what you are referring to, as I too am generally running at about 5-10% emotional capacity. But when an emotion flares up, it REALLY erupts. It becomes the central foci for all thoughts for a while, and seems inescapable.
I've been suddenly struck by this overwhelming sense of desolation and aloneness, even around other people. It always passes, and I've become fairly adept at speeding through this temporary emotional shift.
My only advice is when it happens, hunker down for the duration, don't allow yourself to act on anything you might get in your head until it passes, sometimes thoughts heavily influenced by emotion can be self destructive or at least ill advised, and you may find you do or say something regrettable. Hunker down, isolate yourself if possible, and weather the storm.
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I am Ignostic.
Go ahead and define god, with universal acceptance of said definition.
I'll wait.