I mean, literally snap out of it. That’s what I did for a few months when I couldn’t take the obsessions. I’d wear a rubber band around my wrist, and every time my thoughts would turn to an obsession, I’d snap the band as a reminder. (Fair warning: by bedtime, my wrists were a tad red. Another behavioral technique you could try is to write out the obsession on a piece of paper. Then crinkle it up and throw it away. That way you have literally thrown out your obsession. Or you could try visualizing a stop sign. When your thoughts go there, remember to stop! Look at the sign!