Your spouse is upset. By something you said or did. Even if you are not wrong. No matter how it happened. No matter the intention.
And since you care so much about your spouse and the marriage, acknowledge that you did somehow contribute to their upset.
Later you can ask what you did that upset them so much (tone matters). Later you might learn about triggers and sensitivities. But for now, just apologize for being part of the reason they are hurting.
NOTE: It’s not “I’m sorry IF I upset you” or “I’m sorry that you got upset by this.” It’s full on taking of responsibility. “I’m sorry that I upset you.”