I want to send a message telling those who compare me with my boyfriend's ex-girlfriend that I am.

Let this kind of thing go with the flow. As long as you don't lose yourself, you won't lose your boyfriend. If he really changes his mind, you can let go of such a man freely. Like me, these things are washed away by time. There is a saying: curiosity kills the cat. No matter how curious you are, try to restrain yourself. If you gossip too much, your boyfriend will get tired of you, and maybe you will remind your boyfriend of what happened between them because you often ask her. Since he doesn't want to talk about it, let's all be silent. From what you said above, your boyfriend should have no feelings for him. Don't worry.