Communication is the key, there are personal boundries that both need to take into consideration and work towards.
If this is your second attempt to have him stop doing something you personally don't like (and bare in mind, you can not afford to be in-secure in a relationship, as it almost always fails from doing such things as you are, snooping which then poses questions in your mind that are either true or false only you will never know until something factual happens, therefore, you will always wonder and therefore, your relationship will always be under stress,) and he hasn't acknowledged it as being something that really bothers you, therefore stopped it, as to why you broke up, then will he? Probably not.
Having said that, it is a boys thing so should he stop? If it is only words?
You have to discuss what you like and don't like, why, reason why, and see if it is really your in-security that is the problem not so much his words, or if it is your morals and therefore, you can't accept that type of behaviour in which case, you have to question your relationship.