Easier said than done for most people. As long as the price goes up or remains relatively stable people have tons of confidence, but as soon as the price starts dropping they snap. It means they are gambling, have invested more money than they should have invested, or they invested with borrowed money. These are flyby "investors" who don't contribute to anything, let them exit.

You'll likely feed the whales anyway, whether you're losing or making money, so there isn't much difference here. Let's be honest, most people are here to make profit and to sell at some point. You even pointed it out yourself by stating that it's better to hold out till the price reaches a level you're happy selling at. Whales are everywhere, you can't avoid them.