HOLMES: How long will it be, I wonder, before I'm allowed to live that down? How many times must I say it was an accident?
KAREN: Please, Dana.
HOLMES: I'm going to bed.
KAREN: Please get out of my bedroom.
Captain Holmes and Karen have a clearly terrible marriage. Holmes tries to dismiss the stillborn birth he caused by leaving for an adulterous affair and then getting drunk and passing out while Karen was in the midst of a major problem with her pregnancy. Effectively, he also caused her to lose the ability to have children. Still, here, he's being casual about it—it wasn't an "accident," but the result of his extreme irresponsibility and callous disregard.
WARDEN: No— it's just that I hate to see a beautiful woman goin' all to waste.
KAREN: Waste, did you say? Now that's a subject I might tell you something about. I know several kinds of waste, Sergeant. You're probably not even remotely aware of some of them. Would you like to hear? For instance, what about the house without a child? There's one sort for you.
Warden was trying to hit on Karen—but he accidentally got her to talk about the greatest source of pain in her life, her horrible marriage. (She implies what happened with the stillbirth and Holmes' role in it.) His relationship with Karen is never a shallow affair—from the beginning, it starts to go deep, dealing with the worst crises in their lives.
KAREN: Come back here, Sergeant. I'll tell you the story; you can take it back to the barracks with you. I'd only been married to Dana two years when I found out he was cheating. And by that time I was pregnant. I thought I had something to hope for. I was almost happy the night the pains began. I remember Dana was going to an officers' conference. I told him to get home early, to bring the doctor with him. And maybe he would have… if his "conference" hadn't been with a hat-check girl! He was drunk when he came in at 5 A.M. I was lying on the floor. I begged him to go for the doctor, but he fell on the couch and passed out. The baby was born about an hour later. Of course, it was dead. It was a boy. But they worked me over at the hospital, they fixed me up fine, they even took my appendix out – they threw that in free.
KAREN: And one more thing: no more children.
Warden's been acting like a jerk, pressuring Karen to talk about her other affairs. He's being pretty insecure. She explains that she's not just having affairs with random people for no reason—it's because her marriage is dead on the inside, and neither she nor her husband are in love with each other anymore. They both have a license to see other people.
ALMA: Sit down and—and get comfortable. I'll make you a martini and see what's to cook for dinner.
PREWITT: Hey, this is like being married, ain't it?
ALMA: It's better.
Why is it better? Maybe because it's not like Captain Holmes and Karen's marriage, which is a nightmare. It's just a light, easygoing thing—they're hanging out.
KAREN: Once commissioned, you go to the States.
WARDEN: An officer.
KAREN: Yes. Then I could divorce Dana and marry you.
WARDEN: An officer! I've always hated officers.
Karen wants to leave her lousy marriage and enter a beautiful new one with Warden. But even though Warden loves her, he wants to be true to his own sense of himself. He can't become an officer because he prefers being at the ground level, down with the other grunts. This throws a wrench in Karen's plans.
HOLMES: I ask you once more: I want to know who he is and where you met him.
KAREN: I'm not going to tell you.
HOLMES: One thing I know: I know he's a civilian. You'd be too discreet to pick an Army man.
KAREN: I wonder which is hurt more, your pride or your curiosity.
Karen's comment strongly suggests what they both know: Holmes and Karen don't love each other, so it's only Holmes' pride that might be hurt. His real emotions aren't invested—he's just annoyed at the fact that a lower-ranking soldier might be cuckolding him.