The "disorder" is a description of about how it's causing people pain / trouble in their lives. Experiencing something, and processing it, and it having a lasting impact on your life and your thinking isn't by definition disordered. But having it cause problems in your life, e.g. physical touch from people you trust causing panic attacks, that's a disorder.

Forgetting, as a treatment, may be something some people want.

To my eyes your comment is pretty dismissive ("drug people up"). A little empathy, and an open heart goes a long way here.