After three years, my ex-boyfriend suddenly sent me a message asking how he was doing. At that time, he firmly mentioned breaking up. How is he feeling now?

He is separated by so many years, and then you send this message. The first level of meaning is that a simple young man sends you a greeting message. This message may even be sent in a group. The second point is that this letter message is simply sent to you personally on a one-to-one basis. Then it is possible that he wants to take a look and test your current living situation. If it's the former, you don't need to have too many thoughts or what the disadvantages mean. If it is the second case, then there are two cases. In the first case, he may be single or his current emotional state is not good. The second type is that we want to test your current personal situation. See if there is an opportunity in future communication and contact to seek an opportunity to rekindle the old relationship and reconcile.