The quilts are beautiful and you should call ASAP. When you know they got them, chalk it up to lesson learned and don't even send them a card again. When they bring it up (like they probably will) just tell them why they don't get gifts anymore. With all the forms of communication now, a thank-you should not be a problem. I would be hurt,too. Part of the joy of making it is seeing, or hearing, how happy they are to have it. If you don't feel it's liked, or appreciated it takes a lot of the joy away from you.