In my view you had a moral and most probably, legal commitment to sell.
The buyer also had a commitment to buy, within the set time limit of 1 week set by you, provided you give them the stats. Unlike you, they had one possible reason not to complete the purchase, and you gave them the reason.
You didn't give them a chance to honor their commitment.
Reneging on your word because you have a possible better offer is bad business imo.