After my girlfriend broke up with me, she sometimes sent me a message saying that she missed me and I wanted to get back together with her, but she didn't agree. What should I do? ...

Don't get me wrong, girls like to think. Sometimes after breaking up, they miss you a little. When you are together, your concern and attention to her just shows that you want to get back together with you. But this kind of feeling is usually not revealed by girls, because since we broke up, we just want to forget it. She still sends you these messages from time to time, and she doesn't want to get back together. A little selfish. For example, although you can only marry one wife, you want many girls to love and care about you. In the same way. I suggest you don't get too angry and recognize the reality. You can play a little ambiguous when you are finished, but don't let her affect your contact with other girls.