Okay, you know how in the episode Lexmas Lex was married to Lana , had kids, was still friends with Clark, well i know how most of that could have happend trailing back to Nemesis. Clark realizes that he gave up on Lex to soon, so he apologizes and then , over the next few months finally regain their friendship. Lana falls head over heals in love with the new Lex. It results in most of the stuff happening. I keep saying most because Lex doesn't giver up his wealth and Johnathan is dead.