I had a similar experience, and I'm a bit slow to process extreme emotions so in crisis I'm very calm. A few days later though, it hit me while I was in the shower and my guard was down; I started shaking and I didn't know why. I literally dropped the washcloth and realized that I was crying, then I realized why, and it all hit me. As you say, it's one of those things that never quite heals, it just... skins over a little. Sharing does seem to help.