Being in the Army, and being an NCO, often works well with these things, as showing feelings is often looked at as a weakness. Being able to maintain a stoic front is looked at as being a quite admirable characteristic.
Despite not showing feelings, I do have them. I ran into them in an especially brutal way this past week through having to say goodbye again to my parents and girlfriend. We had a 4-day pass where family could come visit, and at the end as I left back for base, the emotions were indescribable.
In effect, this overload of emotions is easier to hide than the smaller day to day emotions. There is so much sadness or melancholy or whatever feeling it was that I really did not know how to act, and was instead almost in a state of shock. The feelings are so strong that they don't even really coincide with normal feelings.
The best way I can describe this is through an analogy to physical pain. When I was 15 and was accidentally run over by my friend's car while goofing around, the pain was so intense in my shattered leg that to this day I haven't had anything that felt at all in the same way. The physical feeling wasn't of pain, it was of something else and worse. This is like the emotional pain of having to say goodbye again (even though this is the 6th time I've had to say goodbye in two deployments due to the passes and leave from the different deployments that allow you to see your loved ones again).
Now in contrast to that, returning home from the last deployment and setting foot on American soil again (after just about giving up hope of ever being home again) was a feeling of relief and joy that cannot be compared on the same scale to the say the joy of a birthday or getting accepted to college, etc.
I would imagine there are more moments like this through life, perhaps a child being born or marriage, and I am looking forward to more of the positives and less of the negatives. I just need to remember to not block emotions out, and to remind my friends of the same.