WARDEN: You think I'd be here if I thought it was a mistake? Taking a chance on twenty years in Leavenworth for making dates with the company commander's wife? And her acting like—like Lady Astor's horse, and all because I got here on time!
KAREN: Well, on the other hand, I've got a bathing suit under my dress…
WARDEN: Me too!
In the army, adultery with an officer's wife is actually an offense that can get you imprisoned. So, Warden's risk in even meeting Karen Holmes is pretty significant. Also, John Jacob Astor was a famous American tycoon, and acting like "Lady Astor's horse" means being stuck-up.
KAREN: Why don't you tell the truth, you just don't want the responsibility. You're probably not even in love with me.
WARDEN: You're crazy! I wish I didn't love ya; maybe I could enjoy life again.
Here, love isn't actually making anyone feel good—they're both feeling pretty bad because it's only causing them complications (the risk of a prison sentence for Warden, and the difficulties of a divorce and remarriage for Karen).
ALMA: I do mean it when I say I need you, 'cause I'm lonely. You think I'm lying, don't you?
PREWITT: Nobody lies about being lonely.
Alma isn't in love with Prewitt—but she likes him and doesn't want to be alone. Prewitt points out that no one would ever lie about being lonely, because it's sort of embarrassing and sad… and what would be the point of making that up?
WARDEN: I've never been so miserable in my life as I have since I met you.
KAREN: Neither have I.
WARDEN: I wouldn't trade a minute of it.
KAREN: Neither would I.
Love in Warden and Karen's case is an acute mixture of joy and anxious misery. Their whole future is painfully uncertain, but their present is secretly enjoyable.
PREWITT: A man loves a thing, that don't mean it's gotta love him back.
This is Prewitt's attitude towards the army in a nutshell. He loves the army because he's a born soldier. Even if it treats him terribly, it's the place where his life's been able to make sense.