Coffee:
But in Princess Weiyoung , after FL misunderstood ML for death of her family she kept her distance from ML for long time...also both of them were forced to married Second leads....that's reason I end up drop this drama because many misunderstanding.
Coffee is partly correct - there are three instances in The Princess Weiyoung where, after falling for each other, the leads are not together. One of those instances involves a misunderstanding, and another instance stems from a situation where one of them is framed for something they didn't do. However, the last instance is actually an example of the leads trusting each other and working together.
The leads fall for each other not knowing each other's true identities. When the FL learns that the ML is the grandson of the Emperor that she believes is responsible for the annihilation of her family, she turns cold towards the ML because she is bent on revenge against his family and believes they cannot be together. The ML remains interest in and in love with the FL at that time and continues to help her whenever he can. When she finally explains her identity and why they can't be together, he sticks with her anyway and that's when they first really get together. Later on, they find proof that a villainous character tricked the Emperor, so the Emperor did not deceive, betray, falsely accuse, or order the killing of the FL's family.
The second instance is when the FL is framed for killing the ML's mother. Even when there's a ton of evidence against the FL, he cannot bear the thought of her being executed. And once he's over the initial shock of his mother's death, he works on investigating the truth and helping her. Ultimately he is forced to marry the SFL in order to save the FL, and the villain makes him promise not to explain everything to the FL. This leads the FL to believe that the ML has abandoned her, even though he's doing all this to protect her. But the situation doesn't last very long because as soon as the FL is in danger again the ML reveals the truth. The SFL also dies. I don't remember the exact details but iirc she was executed for being the real murderer.
The last instance is when the main villain captures the leads, the ML pretends to go crazy from being tortured and the FL pretends to accept the villain's marriage proposal. But they are both working together to trick the villain, and they make their move during the "wedding" between the villain and the FL. So the FL does not marry the villain, and the leads are not broken up due to a misunderstanding between them at that point. It's the opposite: they understand each other well and are conspiring together.
Basically there's a time when the FL believes they can't be together, there's a time when the FL believes that the ML has forsaken her but he's actually protecting her, and there's a time when the FL has to pretend that she has forsaken the ML but she's actually working with him against the main villain. Apart from the immediate aftermath of his mother's death, the ML always trusts and stands by the FL. He tells her he will stand by her whether or not there is evidence to support her innocence, and it's true.