Sumner Redstone, 85, files for divorce! Why bother?

First, Sumner Redstone ditched couch-jumper Tom Cruise.

Now he's dumping his wife of five years.

TMZ has obtained divorce docs filed yesterday that say Redstone, the 85-year-old CEO of Viacom, has asked for a divorce from 46-year-old Paula Fortunato.

It's only his second marriage. And, according to Forbes, before the economic collapse, Redstone's net worth was roughly $9 billion.

And he only divorced his first wife four years ago! Word is that he has asked Paula to leave the house and she won't. Something about that iron-clad pre-nup that she only gets $1 million if they split. Still, not bad for only five years work.

Oh, did I mention that Redstone cites "irreconcilable differences" as the reason for the split?

What, like she didn't make him the kind of porridge he liked? Or she hated finding dentures in a glass by the bed?

He's 85, for crying out loud. Who's next? Who would want to marry an 85-year-old billionaire?

Oh, right. Every opportunistic woman in Hollywood.

Photos: Gosh, and they looked so happy at the from Vision to Reality event on September 18, 2008>

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