Obviously, Su Xiaofei had no idea about what's going on in Lu Qingfeng's mind, as she wasn't aware that she wasn't the only one who was reborn after their pitiful end in their previous lives. As much as Lu Qingfeng wanted to tell her about it, he feared that it might only drive her away from him.
There's no need for Su Xiaofei to find out about the dirty things he did to avenge her and his ruthless tyranny in their previous life.
It seemed as if Su Xiaofei had this notion that he wasn't the same tyrant he was in their previous life. Although he wasn't sure how much Su Xiaofei could remember from their past lives, Lu Qingfeng wouldn't dare to jeopardize his chance to be with her in this lifetime.
In his first life, because she was so madly in love with Mo Yuchen, Su Xiaofei had come to hate him, refusing to see him or hear whatever he wanted to say when he abducted her on the eve of her wedding with Mo Yuchen.