PIC: Michelle Williams’ Boyfriend Jason Segel Resurfaces

Jason Segel arrives at LAX April 9, 2012  NPG.com

Jason Segel is back in Lala land.

On Monday, the actor, 32, touched down at LAX airport. Wearing a striped sweater and knit cap and carrying a winter coat, duffle bag and magazines, Segel smiled politely for the cameras as he went through security.

It's the first time in awhile that the star (his new film Five Year Engagement hits theaters April 27, with promotional events planned for this coming weekend) has been photographed out and about — but this time, Segel was without new love Michelle Williams. (The pair were photographed taking romantic strolls together in NYC in late March.)

As first reported in Us Weekly, Segel and the Oscar-nominated actress, 31, have quietly embarked on a romance after years of friendship (they share a mutual pal in Busy Philips, Williams' BFF and Segel's costar in cult 1999 TV show Freaks and Geeks).

jason and michelle
Michelle Williams and Jason Segel in New York, March 24, 2012 Jae Donnelly/INFphoto.com

"Romantically, this kind of happened overnight!" marvels one source in the latest issue of Us.

And the duo are trying to make the relationship work despite living on opposite coasts — he in Los Angeles, she in Brooklyn with Matilda, her 6-year-old daughter with her late ex-fiance Heath Ledger.

Although many were surprised by the unexpected pairing, it makes sense to those closest to Williams, who's been hurting ever since Ledger's devastating 2008 death.

"Jason is supersweet," says a second source. "He makes Michelle laugh and feel good about herself."

And Segel himself is ready to change for the better for his new love. "Jason has been trying to be more of a grown-up lately. He is taking care of himself more, exercising, eating right and dressing better. Basically, not acting like a frat boy anymore."

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