Why are some guys afraid to show their feelings?

For me it's a combination of shyness and my fear of being hurt by those I've trusted again. Shyness just makes me clam up and not want anyone to see what's going on with my feelings. My fear stops me because I've been hurt badly by those I've thought I could trust after I shared my feelings with them in the past - things like going and telling someone else I didn't want to know (breaking confidences) or reacting badly to what they've found out.

It's the same reason women do it. They have been hurt before.

Imagine it this way. You live in a kingdom. It is an open kingdom and you have neighbors. One of your neighbors likes you so you openly invite them into your kingdom. One day your neighbor steals from you and breaks something of yours. You now view that neighbor differently. You don't want a neighbor whom you treat with respect disrespecting you, right? So when your neighbor leaves you put up a wall. The next time your neighbor comes over he has to knock before entering.

You stick your head out the window and say, "Who is it?"
He yells up, "It's me your faithful neighbor"
You think, "Yeah right" and you don't open the door. That neighbor eventually moves away.

A week later a new neighbor moves in. Well this new neighbor comes walking up to your door. They knock on the door. You stick your head out and start to get to know them, but do you let them inside? You know the last time you let in a neighbor they stole from you and broke things that meant a lot to you.

You make the decision not to let them in so quickly. Maybe you will open your doors in a week, maybe in a month or maybe a year. The decision is up to you. Your neighbor on the other hand would like to be invited in. They have they decision of how long to wait before they realize they are wasting their time.

Now just think if the guy got hurt numerous amounts of times. He would have a wall, a door, locks and possibly even a drawbridge over a moat with crocodiles. It can go on and on.

I would find out if he was hurt in the past. What happened and try to understand. Don't ask him his feelings for you because that might be the wrong thing to do.

They're afraid of rejection.

They have trouble trying to express their feelings.

It's nailed into almost every guy's head to project an image of being 'tough' and 'unaffected'.