This is what makes the character, his or her emotions ruling actions sometimes. Just like a movie, the reader has to see those emotions coming to life in that book. Don't be afraid to use them to your advantage. Think of all the movies you've seen that brought emotion into play. It wasn't necessarily when someone broke down an cried, but maybe when they didn't.
Mannerism plays a role.
Robert Newton Peck called them tools. Give your character a tool. Tools make sounds. Remember Captain Ahab and that confounded loud thudding of his peg leg. Pierce his ears.