In this case, the only mistake I made was to overlook that a certain verb was written in the past tense, rather than the present. It said ‘knew’ not ‘know.’ I did notice it at the time, but thought it just a matter of American idiom. Today it dawned on me that it was rather more significant.
It changes the whole sense of the e-mail, you see. What I read as saying ‘Your presence in my life is valuable’ actually says ‘The memory of you is valuable, but it’s all over now, Baby Blue.’
Well, at that point you feel a bit foolish, which is why it’s always worth reading things at least twice before coming to any conclusions.