"Spend more time with the family" excuse is code for "I will use my spare time to undermine a nearby Federal Member of Parliament so I can get his seat".
Snake Kean destroyed the Liberal Party's reputation in NSW to the point that he was among the top reasons people wouldn't vote for them.
He undermined and background against conservatives in the Party and did all he could to damage his internal political opponents.
Now that he's driven them to Opposition, he's been given the opportunity to run for the leadership basically because there's no-one else left.
The snake runs and hides.