Although it can seem embarrassing to cry when talking about your problems, it's a completely normal response and is a healthy part of processing your pain. Anticipating crying can cause you to really build this situation up in your mind, and continue to avoid situations that will help you to let out these emotions. Going to someone to trust is a great idea and I encourage you to try this when you can. Have you thought about writing things down before sharing them, or maybe in place of saying them out loud? You could write out an outline or a letter to share with a friend. That could be a way to start letting out what is hurting you without anticipating a breakdown so much at least at the beginning.