I don't think that you should avoid crying, it is a bad but also healing experience that will help you get over your ex. Some people need to cry it out to get over certain things thats what i find helps me. Try to pity yourself and feel the emotions, if you miss him then tell yourself you miss him but you can't go back to that. After a good cry you will feel this amazing clarity/calm. It helps me but maybe its not for others, I don't know