In The Crucible, Miller shows that it is possible for John to rebuild Elizabeth's trust.
Miller is quite skilled in showing that it is not the easiest of things to rebuild trust once it has been broken. Yet, Proctor seeks to do so. The fact that he and Elizabeth do not separate despite his infidelity is one way that Proctor seeks to restore the trust that has been broken. It is for this reason that Proctor sincerely says to Elizabeth in Act II, "I mean to please you, Elizabeth." While it is clear that John wishes to fix what is broken and that Elizabeth wants to make things right between them, Miller shows that rebuilding trust is difficult. This struggle is evident as Act II progresses. Both of them fight through the pain of the past.
In order for both Elizabeth and John to restore trust between them, they have to learn to look beyond the past. Miller shows this emerge in Acts III and IV. When both sacrifice for the other and find one another's "goodness," it is clear that trust is restored between them. It is not the work of a day, but Miller shows that the basis of any successful relationship is the need to work at making right that which might be wrong.