Lohan and Burke had lunch together at the Ivy in Los Angeles yesterday. A witness told British newspaper, the Sun, "Lindsay arrived with one of her girlfriends but then Jamie came along and joined the group. Lindsay had a big smile on her face when she left the restaurant." The paper reports that Lindsay and Jamie left together and went back to her apartment.

Only days before, Jamie was spotted smooching Courtney, though. The pair dined at Mr. Chow on Sunday and left holding hands and kissing. A spy told Life & Style Weekly, "They definitely looked like they were on a date, and they seemed really into each other."

This love triangle has the potential to turn into a square. In January, Jamie was linked to supermodel Kate Moss, who is friends with both Courtney and Lindsay. If things don't work out between Kate and her rumored fiancé, Pete Doherty, perhaps she'll move in on Jamie again too.