As her romance with teen heartthrob JUSTIN BIEBER heats up, Disney starlet SELENA GOMEZ has chucked her "purity" ring – and her parents are fuming!

Selena, 18, was recently photographed getting cozy with 16-year-old Justin in Miami and kissing him aboard a yacht off St. Lucia. The purity ring that she’s worn for six years – a symbol of her pledge to remain pure and celibate until marriage – was nowhere in sight.

"When the ring came off, Selena’s parents became unglued," a family friend told The ENQUIRER.

"Selena got the ring at 12 and never took it off," revealed the friend. "But when things started getting hot with Justin, suddenly she was wearing it less and less.

"Selena’s family thinks the world of Justin and isn’t opposed to them dating. But they’re very conservative people and they’d be heartsick if she did something with him that she’d later regret.

"The family has even gone as far as having people in her entourage report back to them when she spends time with Justin. Selena hates being spied on, and that’s pushing her away from her family."

Ironically, her mom Mandy Teefy became pregnant with Selena when she was only 15.

She split with Selena’s biological father Ricardo Gomez five years later and married Brian Teefy in 2006.

Since early fall Justin and Selena have been spotted cozying up at the movies and high school football games, sharing yogurt and enjoying romantic dinners.

In mid-December, the couple went out together after Justin’s Miami concert. Photos of them kissing aboard a yacht in the Caribbean surfaced in early January. During all the outings with Justin, Selena left the purity ring at home.

Her ring is engraved with the words "True Love Waits."