Mark fossie and Mary Anne had a fight after she went out on an ambush one night with the Greenies. Fossie felt that Mary Anne was becoming too comfortable with the environment and didn't like it. He wanted her to be a perfect girlfriend who was well kept, which she was straying away from. The next morning she was cleaned up, wearing nice clothes, and didn't talk much to anyone.
Man vs. Man
Tim O'Brien threw a grenade at a Vietnamese soldier and killed him. He felt ambushed, as if he didn't have much time to make the decision whether to kill him or not. So he did what his instincts told him, and before he knew he threw the grenade and the man was dead. After doing it he couldn't help but feel guilty for what he did. Even years after the war he still goes back to that moment and fights himself within to try and decide what the correct decision would have been.
Man vs. Self
Tim O'Brien left his home town in a panic after he found out he had been drafted into the war. He drove until he nearly reached the Canadian border where he discovered a lodge, which he stayed at for six days. He left because he needed time to think about what he should do. He didn't want to go to war nor disappoint his family and country. On one of the last days, he went out fishing with the owner of the lodge and was faced with the decision to escape or go to war. If it weren't for the thought that he would be shamed by society for not going to war, he would've escaped the draft.
Man vs. Society
Curt lemon had been afraid of the dentist for a long time. So when the soldiers were ordered to see the dentist, Lemon got so nervous that he fainted before the dentist even got the chance to examine him. He was so embarrassed and ashamed that he went back to the dentist and ordered him to pull out a perfectly good tooth. He did this because he couldn't stand the thought of the others seeing him as weak. He really cared what society thought of him so he went to great lengths to be the way they wanted him to be, or the way he thought they wanted him to be.