Cricket, what a hero you are to me! I am truly inspired by your dedication and service to others. I know you don't do this for recognition or thank you notes, but the lack thereof would wear on the hardiest of souls -- including yours. You must take care of yourself first -- like putting on the oxygen mask in an emergency, only when you are whole and healthy can you help others!
I must also say that people in the throes of severe emotional distress might not be able to write thank you notes. The organizations might not provide your contact information, or they might not pass along anything they receive.
But mostly, I can share that my experiences with *people I know* don't always reflect their true appreciation for the gift of a quilt until well after the fact. For instance, my father in law thanked me for a quilt I made for him last Christmas, but I had no idea until he passed away last month that he used it almost every day! My MIL offered to send it back to me, because it meant so much to him. I gave my parents the first full-sized quilt I ever made, to much thanks, but I didn't see it again for almost a decade. Then, suddenly they'd had it framed and mounted on their living room wall! My sister thanked me for a quilt I made for my niece, but my mother recently told me that's the quilt she sleeps with every day for naps, and every night in bed. I had no idea, and these are people I talk to all the time!
I can understand feeling discouraged by the lack of response, but remember, too, that you've made a difference in the lives of people you'll never even meet, even if they never reach out to tell you so. Even if it just means someone is warm for the first time since winter set in.
*I* appreciate you, and I thank you for all of your hard work. Even if you never make another quilt, your legacy will live on in all of the lives you've touched through the years, and the world is a better and more beautiful place because of the joy you've brought to others.