Lindsay Lohan stole my fiancé and wrecked my life!”

In an explosive NATIONAL ENQUIRER interview, a bitter Breanna Tierney lashed out at the Mean Girls star — who’s fresh out of rehab and embroiled in a new man-stealing scandal.

Lindsay is proclaiming her love for fellow addict Riley Van Giles — a 24-year-old snowboarding ace, who broke his engagement with Breanna after meeting Lindsay in recovery.

The 21-year-old star — who checked into the Cirque Lodge facility in late July after being arrested for DUI and cocaine possession — began a steamy affair with fellow patient Riley, charges Breanna.

“Riley went into rehab to get his life together and in the process meets Lindsay and ruins my life,” she told The ENQUIRER.

“I loved Riley and Lindsay stole him. I met her at a meeting while they were still patients at Cirque, and I just knew something was up.

“She came into the meeting with Riley, and she comes over and sits next to me, being overly nice. She was complimenting me on my hair and trying to be my friend. It didn’t seem sincere at all.

“A few days later, I get a text message from Riley telling me he wanted to ‘take a break.’ I knew instantly it was because of Lindsay.”

The distraught 22-year-old — who supported Riley through numerous busts and his struggle with drug addiction — says he got on one knee and proposed to her almost three years ago.

“I’ve stuck by Riley through the good and the bad,” Breanna told The ENQUIRER. “We lived together for three years and planned on being together forever.

“But when he finally confessed to me that he had sex with Lindsay in one of the stairwells at Cirque — that was it, we were done.”

Breanna fumed, “Lindsay has no morals and needs some serious help — besides drug rehab — for all her other problems.”

Besides his drinking and drugging, Breanna had overlooked other signs that her “Mr. Right” was “Mr. Wrong.”

She was stunned to discover Riley had given her a fake diamond engagement ring.

“I went to get it repaired because some of the diamonds fell out,” she recalled. “I wanted to scream when the jeweler told me the stones were cheap cubic zirconias.”

Pick up the new issue of The ENQUIRER to read about Riley’s police record and see his mug shot.

Riley Giles sunbathes with Breanna Tierney