Guilt wasn’t a feeling she liked. It meant that she had done something wrong. She also felt a twinge of guilt for what she would have to do while undercover, but only a twinge. She figured Clark deserved it. After all the times he had left her in the dark, he could stand in it for a while himself. She decided, though, that the least she could do was wait to tell Clark that they would have to once again slow down their relationship due to her kiss with Superman, and due the mountain of guilt she felt about that, until at least the day after his birthday and until he had found his memories.
I think that last part should be "due to the mountain".
I have really bad feelings about this.
Why do they both have to come up with such bizarre ideas. However I have to say I have more sympathy and understanding of Lois's plans to this point than Clark's. At least she has been wronged by him. Clark, not really at all by her.
