I believe Bingge loves Ning Yingying the most. Not romantically, although it took a long time to realise that, but it is the strongest love he had felt since his mother's death.
She was the love he had before he became so corrupted he could only think of conquest, of inflicting the pain he suffered at the hands of the world onto the world. As the years went by the love he felt for her became so tangled and twisted in revenge and hatred, and is hardly what it was when he was kind, but he is forever aware it is still there.
When he spends months wondering what to do about the Shen that might be out there that could teach him kindness, he has to admit he thought about kidnapping her along with him in hopes that he could pretend to relive their childhood together, but he knows that is impossible.
So, he does his first act of love since sharing that dream together, and let's her go. He gives her the largest share of what he has as emperor, along with a note explaining his decision, something he gave to no other wife. And then he leaves. And they never see each other again.
Ning Yingying does not mourn him. She did that so many years ago, and she's dried those tears. But she does wonder if there is a world where they got to be friends, and nothing bad happened to them. How foolish of her to believe that love was enough. But she is still known as the dumb wife, and while she plans to move forward with her life, taking her children and the money and never looking back, she hopes it was just her love that couldn't save him.
