For whatever reason of her own - whether it was the dark memories she had seen or the need to protect him from herself - Rogue fled, still under the influence of his mind. Concerned about her, Iceman followed her and found her in the middle of a robbing a museum. She was clearly upset by what had happened, and decided that she needed time away from the mansion to work things through by herself. She proposed a road-trip to Iceman, who readily agreed, because he needed to come to terms with his own possession by Emma Frost. (Of course, in a perfect world, she would have stayed with Gambit while he was in a coma, so, unsurprisingly, he felt quite hurt and abandoned.)
Subconsciously led by Gambit's memories, their journey led them westwards towards Seattle. When Gambit discovered their destination by intercepting Rogue's phone-call, he realised that the secret that he had been trying to keep from his new team was finally going to come out:
ROGUE: We're . . . me an' Bobby . . . we're on the road. Ah . . . Ah needed some time away after . . . what happened. A-Ah'm glad to hear ya are up and around, Gambit.
ICEMAN: Rogue! Today, huh?
ROGUE: Remy, Ah have t'go . . . We're tryin' to make it to Seattle before it gets dark.
GAMBIT (THINKING): . . . She knows. O' course she knows . . . She was inside my head when we kissed! In a last ditch attempt to salvage the situation, he flew to Seattle to try and stop the truth from coming out . . . .