The former Cheetah Girl - who used to date Rob Kardashian - confirmed to Us Weekly that she had ended her six-year relationship with Lenny, who is a music exec at Roc Nation.
Adrienne told the magazine that although she's sad at the break-up, she's thankful for their time together and insists they remain close friends.
"Six years is a long time to be together, but we had to make the decision to go with our hearts and not be embarrassed or afraid of change. He absolutely helped make me a better person and I will forever cherish the time we shared together."
Adrienne, 31, announced her engagement to Lenny, 44, in February, sharing a photo to Instagram showing herself flaunting her engagement ring while Lenny kissed her cheek.
Her caption read: " "YES! I will soon be Mrs Lenny S!"
The couple began dating after Adrienne split from Rob Kardashian in 2009. Their relationship had been documented on Keeping Up With The Kardashians. They even had tattoos of each other's names inked on their bodies, although Adrienne revealed last year she was having hers removed.
"I thinking living the last six years with somebody's name on your body is a little weird and that's more painful, like, you know, to have to explain it to my kids," she told Extra.
"People are always like, 'Isn't it offensive to the new man in your life that you have someone else's name on your body?'"
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