There is no reason for love in the first place, or it may be wishful thinking or mutual love.
The only time Zhang Xia was wishful thinking was when Zhao Jingzhi was already in love with another man.
If Zhao Jingzhi was Zhang Xiawei's doom, then Zhang Xiawei would be happy to go through fire and water for her, just because he had known it for a long time.
He had to be her.
It doesn't matter, it really doesn't matter. He is waiting for her love to wake up.