I misread the per mile cost for transferring Delta miles. They are ridiculously high, but in my haste, I thought they were telling me the value of the transferred miles and I was just giving them my cc information to pay the more reasonable transfer fee. I usually read very, very carefully, but in this case, I managed to skip over the most important (or at least the most expensive) details. You cannot get this reversed, even if you call within seconds of the click. The cc gave me the money back and Delta just charged it again.
As if that wasn't enough, while making the transfer, the ticket price actually dropped, so DH already had enough miles without the transfer. We just paid a couple hundred dollars to move miles from my account to his for no apparent reason.
And then, the trip itself, which was supposed to happen last month, was cancelled.