Is your motivation validation or learning? If it's learning, each day will be a win...even if your user metrics are trending downwards. If it's validation, your motivation will fluctuate with your traffic patterns.
What if you just want to make some friends in open source? Truth is I've programming alone for over a decade. Loneliness is a crushing feeling, it feels like nothing matters and that everything is pointless. Recently people started generally interacting with my projects: creating issues, emailing me, I even received my vert first pull request. It feels really amazing, a very welcome change and also extremely motivating. Not sure if I'd call it "validation" though.