Last week while cleaning out the flower beds.. I noticed a robin nest with 3 eggs.. we were gone for a couple days.. upon returning home.. I checked the nest and there is only 2 eggs and they were covered in rain droplets.. I have yet to see the robin sitting on the nest??? Could she have abandoned them??
Yes, it is possible that the nest has been abandoned. There are various reasons that this will occur, but given that one egg is gone there may have been a predator that took the egg and caused the female to abandon the nest. Many songbirds can re-nest, so if a nest is susceptible to predation, it's better for the birds to abandon that nest and try again somewhere else.