Britney Spears Reveals Who She Cheated on Ex Justin Timberlake With

Britney Spears is finally coming clean about her "Toxic" behavior during the early 2000s.

In her upcoming memoir, The Woman in Me, which releases on Tuesday, October 24, the pop star is set to reveal never-before-told details about her tumultuous past — specifically shedding light on her famous relationship with Justin Timberlake from 1999-2002.

In the tell-all transcript, Spears reportedly confesses to hooking up with dancer and choreographer Wade Robson while she was dating Timberlake, a source spilled to a news publication.

The "Circus" singer describes a specific moment during her relationship with Timberlake when she found herself dancing and making out with Robson at a Spanish bar.

After the incident, Spears said her and the *NSYNC frontman "agreed to move past" her unfaithfulness since she was "loyal to Justin" and "only had eyes for him" outside of the one moment of weakness, the insider explained.

While this is the first time Spears revealed the full truth about her scandalous behavior, fans of Timberlake have speculated for more two decades that the "Gimme More" hitmaker cheated.

Many admirers of Timberlake were convinced his 2003 song "Cry Me a River" was about Spears' infidelity during their relationship, as the music video for the tune portrayed a woman who looked like the Princess of Pop and hinted at someone cheating.

Now, however, Spears has not only come clean about her actions, but accused Timberlake of doing the same with another celebrity female, as OK! previously reported.

The mom-of-two decided not to reveal the woman's identity, as she did not want to embarrass or bring attention to her since she now has a family of her own.

And if there weren't enough bombshells, Spears dropped another shocking secret about her relationship with Timberlake — admitting she had an abortion after the pair had gotten pregnant.

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"I loved Justin so much. I always expected us to have a family together one day. This would just be much earlier than I’d anticipated," Spears expressed in an excerpt released from her highly-anticipated memoir.

"But Justin definitely wasn’t happy about the pregnancy. He said we weren’t ready to have a baby in our lives, that we were way too young," the award-winning artist noted. "I’m sure people will hate me for this, but I agreed not to have the baby. I don’t know if that was the right decision. If it had been left up to me alone, I never would have done it. And yet Justin was so sure that he didn’t want to be a father."

Timberlake had been worried about what Spears would unveil about their past in her explosive memoir.

"Justin’s not going to be happy," a source previously confessed, noting Spears "goes after him hard."

Us Weekly spoke to a source about Spears admitting to cheating on Timberlake with Robson.