Maybe there is a connection that I'm not aware of. Allowing myself to entertain feelings for (become infatuated with) a person who was clearly unavailable for a relationship, but in close proximity otherwise, was an attempt (albeit unrealistic and misguided) to allow myself to think about having some emotional life beyond my marriage. I was surprised that I finally started feeling good about everyday life when I did give myself that permission - even if it was purely internal.
Well, thanks again for the advice, which I will take and give this thing time to work itself out.