Complex sentence: She helps Taeko when she has a nervous breakdown at Satoya and when her mother Harumi begins to show signs of Alzheimer's disease, Jun and Itoshi try to care for her despite the actions of Jun's seemingly uncaring father.
Split into simpler sentences: She helps Taeko when she has a nervous breakdown at Satoya. And when her mother Harumi begins to show signs of Alzheimer's disease, Jun and Itoshi try to care for her despite the actions of Jun's seemingly uncaring father.