Tragedy struck the couple back in November when the singer miscarried at six months, but a Christmas engagement signalled a fresh start for the pair.
But when the 25-year-old posted a picture of her freshly manicured hand on her blog a second ring was visible above her engagement ring, Us Magazine reported.
She gave no hint that she is now Mrs. Cooper, and said simply, 'A girl can't do Manhattan sans manicure.'
Meanwhile, a friend of the star told the website that the events of last year made them stronger than ever. 'Their painful loss only brought them closer together,' the source said.