Your art is your art. If anyone harshly criticizes you or attempts to invalidate you or your work, don't worry. They're just giving you a free tour of their personal prison. They're just showing you around the place, pointing out the various chains and shackles that keep them restrained. Speak a silent prayer for their freedom, turn around, and then walk out the door. Their torture chamber doesn't have to be yours. You never have to stay.