Parsons married Helen Northrup, the sister of Jane Wolfe, solidifying his connection to the Thelemic community. Helen, also known as Lilith within Thelema, actively participated in Parsons' occult practices.

Parsons became entangled in a complex relationship with L. Ron Hubbard and Sara Northrup (Helen's younger sister). Hubbard moved into Parsons' mansion and, according to some accounts, manipulated Parsons and eventually eloped with Sara, taking a significant portion of Parsons' savings.

The tumultuous events surrounding Hubbard and Sara Northrup led to the divorce of Jack and Helen Parsons in 1947. This marked a period of significant personal turmoil for Parsons.

Parsons married Marjorie Cameron, an artist and occultist. Cameron became a central figure in Parsons' life and artistic expression. Their relationship was deeply intertwined with their shared interests in Thelema and the occult.

Parsons and Cameron's relationship was intensely passionate and unconventional, marked by shared artistic and occult pursuits. However, it was also characterized by periods of instability and separation.

Parsons maintained friendships with several key figures in the scientific and occult communities. These friendships provided him with intellectual stimulation, emotional support, and collaboration opportunities. Key friends included Ed Forman, Frank Malina, and later, figures within the Thelemic community.