Give someone a full map of your buttons, and eventually somebody presses every single one to see what happens.

Telling someone exactly what hurts you hands them a set of controls. Most people never use them, and the ones who do usually reach for them mid-argument rather than out of malice, which does not make it hurt any less. Trust gets built in stages for good reason.

Share the sensitive parts of yourself gradually and watch what people do with the small things first. Someone careful with a minor confidence tends to be careful with a serious one. Keep the deepest material for the few who have already shown you.