I truly believe that people don’t see any ramifications when they simply don’t respond. They don’t think of the other person’s feelings or think they will cause more harm by rejecting someone.
Either way, I don’t think it’s the best option. People deserve answers. Human connection is a complex, beautiful gift we have and to take it for granted is sad.
I am sorry that happened to you. But at least you know she isn’t the one for you.