What made Emma reveal her disguise in chapter 3

Emma, as Franklin, had become close to the wife of the chaplain, Major Butler, who volunteered her services to the wounded soldiers and who brought them special treats. The tears began to gush from Emma as she told Mrs. Butler about James' death. One thing led to another, and soon she confessed her masquerade to Mrs. Butler. Mrs. Butler was shocked but had no intention of turning Emma in. She had come from a rugged pioneer family and understood that spirit. Mrs. Butler had the notion that if she were younger, she might be doing the same thing. Emma felt better after her talk with Mrs. Butler—she had so much bottled up inside that she hadn't been able to share with anyone.