Why would I seek emotional support from someone so disconnected from their emotions they can't show more than a "modicum" of vulnerability?
How could I trust someone's resilience when they don't show they've been through things that built that resilience, and demonstrate it?
How can I trust someone who so closely monitors how much and what sort of emotions to show to me?
Why are you assuming that someone who sensibly refrains from overly impulsive behavior wrt. showing their emotions (this is what "self-monitoring" ultimately means: we all do it in all sorts of social contexts, and it's a normal part of being a healthy, well-adjusted person) must necessarily be "disconnecting" from them altogether and lacking in emotional resilience?