My ex-boyfriend suddenly sent me this short message, but I didn't reply. What does he mean? Will he contact me again?

He can't let you go, and he still misses you, but it hurt you a lot at first. You should tell him you're fine. If he still comes after you, if you have him in your heart, accept him, but be reserved and don't forgive him too easily, otherwise he won't cherish you. But there may be other misunderstandings. Don't miss the fate, love you and support you.