You can protect yourself so thoroughly that nothing meaningful can reach you.

Defences do not discriminate. The habits that keep out disappointment, rejection, and hurt also keep out closeness, surprise, and being genuinely known, because those arrive through the same opening. A life sealed well enough to be safe is also sealed against most of what makes it worth having.

Look for where your protection has become total: a topic you never discuss, an emotion you never show, a level of closeness you never permit. Then let one small thing through on purpose with someone who has earned it. The exposure is the point, and it is also the only route to the thing you have been missing.