Answer to your question

In my opinion, if you are missing someone, you should tell that someone that you missed them. Because by telling someone you missed them, it will make them happy and appreciate you more. There is nothing to be shy about because there is nothing bad to comment if you say you missed someone. Nothing bad could ever happen. The person will feel that you are a good friend and never forgets him/her. There is nothing to lose here. It will never hurt both of you, it will only make things better and clear.