Maybe i should watch s2 again, because i didn't in a while. But as far as i remember, Nick never had any loving feelings towards Krystle. Maybe some kind of friendship or he felt sorry for her that she was with evil Blake, but love? I don't think so. So why would he come back for her? I really think Matthew makes more sense in that matter, as he really loved Krystle.
And if they couldn't get Hopkins back, they should have called Hamilton in, as Joel would be my 2nd choice here, with his psychopathic fascination for Krystle. He could have brought that Danielle Steele book she had up there, so they could finish reading it together ... remembering those good old days up in the attic. Kind of romantic, isn't it?
And by the end of episode 2, a vengeful Rita stormes in to shoot him and gets arrested.