Cheese, Cues and Blood - S6-E4
Continuity mistake: When Kelly shakes her head no to the guy she is playing for $10,000, he misses the shot and the ball stops at the far end of the table. When Kelly goes to take the next shot for the win, she is hitting the cue ball from the other side.
Answer: It's implied that Steve filed for divorce since in s04e16, "You Gotta Know When to Hold 'Em", Marcy says that Steve is suing for alimony. Alimony is something that has to be requested when filing for divorce. Although the show doesn't spend time on the actual legal proceedings of their divorce.
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