How does Susanna reveal that she remains faithful to Figaro?

In The Marriage of Figaro, Susanna remains faithful to Figaro throughout the plot. Her apparent flirtation with Count Almaviva is a calculated ruse designed to trap the Count and expose his philandering, rather than a genuine betrayal.12

Susanna demonstrates her loyalty and commitment to Figaro through the following actions:

• Strategic Deception: With the Countess, Susanna orchestrates a plan to catch the Count in his own schemes. She agrees to a tryst in the garden only as part of this trap, with the Countess planning to impersonate her during the meeting.2
• The Pin: To confirm the Count's agreement to the meeting, Susanna and the Countess seal a note with a pin, which the Count is instructed to return as a signal.2
• Reconciliation: In the final act, after Figaro realizes the identity of the woman in the garden—who is actually Susanna disguised as the Countess—the two tenderly reconcile, confirming their mutual love and trust.1

Ultimately, Susanna uses these maneuvers to outwit the Count and secure her future with Figaro.12