I'm new to the message boards, but this idea has been in my head for a while.

Lois and Clark meet when they are younger, maybe when Lois visits a relative in Smallville or moves there or some other way. Anyway, they fall in love, get married and move to Metropolis to start working at the Daily Planet.

They're happily married for a few years when Lois meets Lex Luthor during for an interview and he likes her. He then continues to try and get her to be with him instead of Clark.