Complex sentence: She's new to Abigail Adams Jr. High, but soon became close friends with Maeve and Charlotte, then joined the BSG, despite Katani and Avery's cold reactions to her at first.
Split into simpler sentences: She's new to Abigail Adams Jr. High and soon became close friends with Maeve and Charlotte. She then joined the BSG, despite Katani and Avery's cold reactions to her at first.