Men are rewarded in our society for ignoring their feelings, except for anger. When emotions overwhelm a man and tightly wrap around his gut, he certainly knows something is wrong--but he will struggle if he attempts to label those feelings or articulate the cause--especially when the emotions are still in play. Lacking control, he looks down on himself with disdain because he believes it's a flaw to be a man without control. As that tight ball of emotion begins to uncurl and subside, as he feels that he's gaining mastery of himself once again, he has the opportunity to gain a handle on defining the emotion he is experiencing.
But if a partner puts a spotlight on those emotions, while he's in that uncomfortable place, the man may try to hide even more. He's not in control of himself and thinks he should be. The spotlight makes that all the more obvious. If she can restrain herself, it's possible to slowly draw the emotion-averse man out of his cave by building his confidence... by encouraging him to believe that he is able to handle the uncertainty. The passage of time, emotional space, and distractions often provide healing for him... and perspective.
Before the man moves completely away from that raw sensation in his gut, there's a brief period of realization where he can catch an authentic glimpse of himself and his emotional limitations. In that moment he can catch a glimpse of who he is--or go right back to repeat the cycle.