It seems Lindsay Lohan's reported tumble down the 12 steps wasn't the only drama kicked up during her club-hopping weekend in New York. The night before the impulse-propelled starlet was spied downing Red Bull and vodka at the cheese-tastic Hawaiian Tropic Zone, she supposedly got into a scrap with an Olsen twin.

The New York Post says Lohan was hanging with ever-present bosom buddy Samantha Ronson at hot spot the Beatrice Inn Friday when her possessive side popped up.

"Ashley Olsen said hello to Sam at the Beatrice," a mole tells the paper, "and Lindsay screamed at her, 'Get your 15-year-old "Full House" a-- away from my girlfriend.'"

That's one way to ward off an Olsen.

Anyhoo, the following evening at the Hawaiian Tropic Zone, the thrice rehabbed, twice DUI-busted fading star purportedly became peevish because she felt Ronson, who was deejaying at the club, "was ignoring her" (LiLo somehow squeezed in this ostensible annoyance between her reported quaffing, smoking and doing "full body rolls" on the dance floor).

"Samantha was really focused on her work," explains the source, "and didn't leave the booth for anything."

Meanwhile, Gawker has uncovered a Facebook profile that may or may not belong to Lohan. Listed under the name "Lindsay Ronson," the listing features an entry posted just a few hours after paparazzi snapped the actress looking completely party-pooped as she left the Zone.

Lindsay Lohan rests after a night of partying at a New York nightclub, April 2008

"Don't believe the hype," reads the message. "I'm taking my sobriety seriously, and day by day. It was 4:30 a.m.!"

But is Lohan, who was back in Los Angeles this week (she and Ronson hung out Wednesday night with Nicole Richie and Joel Madden), placing the blame for her most recent face plant off the wagon on her repellent parents?

Finger-pointing sources tell TMZ.com that their recent antics, including launching a reality show with Lindsay's little sister Ali (mom-ager Dina) and talking to any media outlet that will listen (dad Michael), are why she slipped up on Saturday night.

They also insist she's committed to her sobriety and has even asked for a "sober companion" on the set of her new movie.

The insiders then go on to justify her late-night club outings, claiming she continues to make the rounds because of Ronson's DJ duties and is only "there for Sam, not the scene."

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