After months of hints, Lindsay Lohan has finally confirmed the worst-kept secret of the year: she and constant companion Samantha Ronson are, in fact, a couple.The confession came on Monday night's episode of the "Loveline" radio show, when Ronson called in to discuss her pal DJ AM, who is recovering from severe burns following a plane crash last weekend.After Ronson chatted for a few minutes with Stryker, the show's co-host, Lohan hopped on the phone for what turned out to be a revealing interview."You guys, you and Samantha, have been going out for how long now?" the host asked. "Like two years, one year, five months, two months?" he pressed, while Lohan paused and giggled nervously."For a very long time," she finally replied."I hope you guys stay together. You're a very lovely-looking couple," Stryker told Lohan. "Thank you very much," Lindsay said.Lohan and Ronson have been living together since May, but have played coy about the nature of their relationship. Lohan jokingly referred to Ronson as her "girlfriend" back in July during one of Ronson's DJ gigs, saying, "My girlfriend won't play my songs."Lohan also got a star constellation tattoo to match Ronson's, which she pointed out in an interview with Marie Claire magazine.The inseperable pair are rumored to be headed down the aisle later this year. "By the end of the year, my love will be Mrs. Ronson," Sam reportedly announced while DJing at L.A.'s Chateau Marmont. A rep for Lohan denied any marriage plans.