Hazrat Ali (Radhiyallahu Anhu) wishing to marry the daughter of Abu Jahl

Q: There is a hadith about Fatima (radhiyallahu anha) being offended of Ali (radhiyallahu anhu) taking Abu Jahel's daughter as another wife. Is it because he was marrying a disbeliever or it's because of taking another wife besides her? And our Prophet (Sallallahu Alaihi Wasallam)'s saying whatever troubles Fatima (radhiyallahu anha) also troubles him. Is it about taking another wife? What teachings should we get from this hadith?