Silver Fox was the love of Logan's life. She was also the sister of Emma Frost, a mutant being held on the island as the prisoner of William Stryker. Silver Fox was a mutant who could control the minds of those she'd had tactile contact with. She made a bargain with Stryker hoping to get the freedom of her sister. This meant meeting and seducing Logan.
What she didn't count on was falling in love with her 'mark'. She was used to manipulate him. They even injected her with a drug so as to convince Logan that Sabertooth had killed her. It slowed her heart beat to the point it was nearly nonexistent. This pushed him into getting the Adimantium placed in his system.
He eventually discovered the truth that she was alive. This left Logan feeling betrayed but she tried to explain the truth. However, they both learned that they were refusing to release her sister.
In the end she was shot and died with Logan nearby. Her last act was to order Stryker to walk until he bled which he carried out.