WHAT BEN AFFLECK and wife JENNIFER GARNER don’t want YOU to know about their VERY private lives!

They're caught in a real-life sit­com – and Jen jokingly calls them the new Lucy and Desi!

Affleck, 41, who is prepping to play Batman, has turned his domestic life into an “I Love Lucy”-style comedy as he fidgets and fumbles while trying to kick his smoking habit, say sources.

“Ben’s promised to ditch the butts again, but now he’s just a bundle of nervous en­ergy and is doing anything to keep his mind off cigarettes,” revealed a friend.

“Jennifer thinks it’s cute and says she feels like she’s Ricky Ricardo to Ben’s Lucy. He comes up with all sorts of household projects and cockamamie schemes to stay busy, and it’s one misadven­ture after another.”

The friend says Ben has tried his hand at repairs, gardening and carpentry at the Los Angeles home he shares with “Dallas Buyers Club” star Jennifer, 42, and their chil­dren Violet, 8, Seraphina, 5, and Samuel, 2 – and nothing has come out right!

“Ben decided he needed to keep his hands busy, so he built a bookshelf for the girls’ playroom,” the source said. “It wound up comically lopsided, with the books tumbling off of it. They ended up hiring a carpenter to rebuild it from scratch.” In other wacky incidents, Ben mistakenly created a rose garden on the wrong side of the house, cleaned a car that had just been detailed – and acciden­tally locked his keys in the vehicle.

Still, sources say Jen is giving her husband an A for Effort as he tries to kick a smoking habit that’s persisted for some 25 years.

“Jennifer says she would not be in a marriage like this with any other guy,” said another pal. “Ben’s the love of her life, but he also drives her crazy – just like Lucy drove Desi crazy.”