With respect, "this shit" and "drove ME crazy" don't sound all that empathetic. This is a disorder that people can't help, and are often very embarrassed by. I think the right way to handle it is to be supportive in trying to help get treatment, while making clear it has zero impact on how you view them as a person.

Not saying you're not doing that, but just a good reminder. I have someone close to me that suffers from this (and is embarrassed by it) and it's helped both of us to sort of view it as a biological quirk/defect (like wearing glasses) vs something really shameful.