How would you summarize Abigail's prior relationship with the Proctors, Act I?

Abigail Williams previously occupied the position currently held by Mary Warren in the Proctors' household.  She would have helped with the cooking and washing, and the children, especially in light of Mrs. Proctor's illness following the birth of her last child.  However, it is clear that Abigail and John Proctor had more than just a physical relationship.  In Act One, when she insists that she has "a sense for heat [...] and [his] has drawn [her] to [her] window, and [she has] seen [him] looking up, burning in [his] loneliness," he admits to her that he "may have looked up" at her window.  He further admits that "[he] may think of [her] softly from time to time."  And although Proctor promises that he will not reach for her again, he has clearly admitted enough to confirm Abigail's belief that he loved her when Mrs. Proctor fired her and "[he does] now."  Thus, their "prior relationship" is still, in some way, present.