What does it mean that my boyfriend suddenly texted a month before breaking up and then didn't return?

Don't think that he sent you a message because he still has feelings for you. Maybe it's just a group message or a joke with a friend, or he has bad taste and wants to see your reaction. It's best to keep it a secret. Maybe someone else has a new girlfriend. I don't know what kind of person your ex-boyfriend is. If you are nice, you may really send it in groups or be teased by your brother. It's best not to post it, so as not to cause trouble. If he is scum, leave him alone. Also, you should know clearly what feelings you have for him. If you don't like him, be friends. If you still like him, you can pursue him appropriately. If he really has no feelings for himself, don't be persistent. Of course, you should also ask your trusted girlfriends what they think of him. Don't be carried away by sweet words.