This has happened to me time and again, Donna. The last time it happened, it was exactly the same scenario as yours. I was actually putting the cat into the carrier and we were going to the new family when I thought I'd check email one last time before I left and there it was, the email telling me that they changed their minds, not even the courtesy of a phone call. I guess they lacked the courage to explain themselves. The only consolation to me and the poor cat was that this obviously was not the right home. But later, a gentleman took the cat and was so conscientious, wanting to know if it had all its shots, etc. So take heart; the right home is out there. You're just having to separate the wheat from the chaff.