He couldn't handle his feelings well, so he ran away from them. Both figuratively and literally. She was trying to catch up to him, to explain things to him, but he was too fast for her. And even if she did catch up to him, he wouldn't listen.
Hine-nui-te-pō ("Great woman of night") is the chthonic Goddess of Night and Death and the Ruler of the Underworld in Māori mythology. She is a daughter of Tāne. She fled to the underworld because she discovered that Tāne, whom she had married, was also her father. The red colour of sunset comes from her.