Photo Credit: Polaris

Just days after reports surfaced that their marriage was in danger, Jennifer Lopez and Marc Anthony enjoyed a romantic dinner at the Luau restaurant in LA on Dec. 16. "They were so cute," an onlooker tells Life & Style. "They looked like they were definitely celebrating something."

But more likely they were making up after having an argument. On Dec. 8, two days after Marc, 40, partied at Tao Nightclub in Las Vegas with J.Lo's pal Eva Longoria Parker, 33, Jennifer, 39, showed up for the LA premiere of The Curious Case of Benjamin Button without Marc -- and without her estimated 8-carat diamond engagement ring and wedding band.

For more on J.Lo and Marc's marriage problems, pick up the latest issue of Life & Style, on newsstands now!