I think you could also take this from the perspective that Proctor is doing the right thing in terms of his beliefs in God. He is not lying about his predicament on earth, but rather is telling the truth, knowing that the reward is coming to him in heaven. If you look at it from that perspective, you can get into the strength that his faith provides him and how much it means to him throughout. That strength comes in the form of his beliefs. Most of the other people of Salem have confused themselves about their beliefs, but Proctor hasn't. He takes strength in that. He falters, but ultimately makes the right decision. I think he also feels a sense of leadership toward the others. He is the most upstanding/strong/powerful person in the group that is hanged at the end. He is the one with the most to lose upon his death. Yet he still does the right thing.