Complex sentence: Their relationship was highly volatile--marred with drug and alcohol use, and physical fights--however the band's manager, Vince Lovegrove, later stated that the nature of their "weird" relationship was the "magic of Divinyls".
Split into simpler sentences: Their relationship was highly volatile--marred with drug and alcohol use and physical fights. However, the band's manager, Vince Lovegrove, later stated that the nature of their "weird" relationship was the "magic of Divinyls".