Complex sentence: She often made frequent visits to New York where she had an affair with Richard Hell, befriended Nancy Spungen, and participated in the local burgeoning punk rock scene; however, by the early 1980s, she was no longer part of the groupie milieu.
Split into simpler sentences: She often made frequent visits to New York where she had an affair with Richard Hell, befriended Nancy Spungen, and participated in the local burgeoning punk rock scene. By the early 1980s, she was no longer part of the groupie milieu.