Emotions are constraints, responsibilities, and no freedom. This is Luo Shan's reason for rejecting feelings. Her mother is a close relative and cannot be let go, but she does not want to give her feelings to anyone anymore.
Ji Yang spent nearly thirty years rationally and indulgently, and found that the only way to trap Luo Shan was love, so he gave up his love just to keep Luo Shan, who always wanted to escape him. He was willing to grant her freedom in exchange for an eternal position beside her.