Complex sentence: They decided to leave when they discovered Terry wanted to support Andrea, she didn't want to be a member of the Duckworth family and decided she would go to university while her mother Connie would raise the child.
Split into simpler sentences: They decided to leave when they discovered Terry wanted to support Andrea but she didn't want to be a member of the Duckworth family. Instead, she decided she would go to university and her mother would raise the child.