Vivian

YH is the one that created problems. He lied his way to her heart and continued to lie even when she is pregnant. Why should she trust him when all he does is lying and hiding? And you expected her to siting still when husband and the only man in her life is dying? It'd make less sense if she did. Susu was frightening and knew nothing when she was captured like us as viewers, she can't win with those immortals that want to kill her and YH knew that too yet he couldn't be there for her and helped due to his lack of judgement. And you think she is irritating? She is pregnant and isolated, and live in "hell" and the love of her life can't even be there for her openly, yet you think it's her fault? If YH never approached her, none of this would have happened

The cold one is actually YH. He is only warm and passionate with BQ and Ali. YH is cold and ruthless with others
BQ is aloof and carefree. She is actually kind as she gave XN her face and saved her yet XN stole LJ and harmed MY. She also saved SX and took her home and eventually saved her son... even SX ran away with her fiance.
It's just BQ doesn't usually forgive people who wronged her nor she is easy to attach.

The drama obviously tried to make the male lead look good and become the center of the story. Mark was wonderful but let not ignore the production did everything to hide YH's flaws and make him a better character, even by making the female lead look bad. YM did well fine for what she was given and required. If one read the book and script, you can see how much character was cut out scarified for the male lead to shine. Put it this way, the drama is YH's POV while the novel is BQ's POV