So I sent JetBlue the email below, which pretty much sums up the situation, and they were gracious enough to change my itinerary! There was a cost variance for the Extra Room seats on the new flight compared to the old, but other than that, nothing. JetBlue rocks!
"Hello! First, let me apologize for being a man, as my wife would say that is what got me into this predicament. However, it was with the best of intentions. Planned a vacay down in Key west with my wife to celebrate our 25th anniversary. Booked flight down first, then recently booked the return flight. But, being a man (as my wife would say), I did not realize we are flying BOS to PBI, and out of FLL to BOS. Now I have no issue with the extra hour driving from PBI to Key West as opposed to FLL, however, I feel my wife would find more misery in that additional hour of driving then she has in our 25 years of blessed marriage. To make things more complicated, I know she would find more misery in paying $150 change fee for our tickets. So, I admit. I screwed up. Not the first time, won't be the last. Any chance I can change our tix out of BOS to FLL, with no fee? I haven't told my wife anything yet. My 25th anniversary happiness is in your hands... "