If this background and signature are his feelings, judging from the lyrics, it may be that he has been hurt, but he can't let go of the person in his heart, so he has such a signature. You said the signature was good, which means he is not sad, but I don't think so. It is impossible to be together, but he is still willing to protect someone. There is helplessness, disappointment and sadness, how can it be good?

Seeing that you called him ex proves that I am right. He should have been broken up and couldn't let go of his predecessor.