He could tell from that video that Qiao Liang cared about Xiao Rou so much that he even began to restrict Xiao Rou's freedom. That could be suffocating! And Qiao Liang said he didn't need her to save him at all and she made decisions above herself, which hurt her. He could tell from the way Xiao Rou looked at Qiao Liang that she loved Qiao Liang very much. If he were Xiao Rou, he would be mad too if Qiao Liang said those words to him, let alone Xiao Rou. He had investigated Xiao Rou who after experiencing a lot more than ordinary girls, must be more sensitive. She lacks a sense of security and needed to be treated with care.
Qiao Liang's words must have deeply hurt her.