The British singer alleged she was assaulted in 2016 by a music industry executive in her 2018 autobiography "My Thoughts Exactly."
Speaking on the BBC podcast "The Next Episode," released Friday, she said: "I do feel like my career has been f**ked with as a result of talking about this stuff."
"On paper, the album that I released last time round, 'No Shame,' was the best reviewed album that I've ever had, and all the shows that I did were sold out, pretty much, apart from the ones in America," she said.
"But I did not get a particularly good run at festivals this season. I didn't get particularly big gigs offered to me. I didn't get a big marketing push behind my album campaign, even though it was probably the best record that I've ever written."
Warner Music has not yet responded to CNN's request for comment on Allen's suggestion that she hasn't been supported in her career since speaking out about the alleged assault, but in an earlier statement to CNN, a spokesperson said the company takes allegations of sexual misconduct extremely seriously.
"It's always coming down harder on the victim than it does on the perpetrator as far as I'm concerned, and people are always questioning what the victim's intentions are or what it is that their sort of endgame is," Allen said.
"I think the victims just want validation. They just want someone to go, 'Yeah that happened, that was wrong. You're a person. Somebody crossed a line with you,'" she continued. "For me, that's all I ever really wanted and something that I never got."
Allen said she was assaulted after attending a party with the unnamed executive, who she said was "in a position of responsibility." Podcast host Miquita Oliver said Allen had further stated in the interview that his identity was well known in the industry.
"He'd got me out of this party and had decided that he wanted to take me back to my hotel," Allen said. "We got to my hotel, I couldn't find my room keys, so he was like, 'Well, why don't you sleep in my bed while I go and get the keys?' or whatever. So I passed out in his bed."
"The next thing I knew I woke up and he was in my bed, naked, slapping my bum and trying to insert his penis into my private parts," she said. "I recoiled and I got up out of the bed and I screamed."
"We ended up meeting up in LA and he acknowledged that what he'd done was wrong. He asked me not to tell anyone about it; he said that if his girlfriend found out that she'd be distraught."
"I do remember immediately while it was happening thinking, even though I'd never met his mom, I was thinking about his mom and how she would deal with the news that her son was a sexual predator. I was prioritizing everybody else in this situation except for myself," Allen said.
"I made a decision that I didn't want to go to the police, I didn't want to make a fuss," she said. "And I wanted to keep it quiet. But I did want to protect myself."
Allen said she went for dinner with one of the bosses of her record label, Warner Music UK, about a month after the book was released. When Oliver asked her, "Did he say, 'Now that we know, boy are we going to do something about it'?", Allen responded, "No."
In its statement to CNN, Warner Music said: "These allegations (from 2016) are appalling. We take accusations of sexual misconduct extremely seriously and investigate claims that are raised with us. We're very focused on enforcing our Code of Conduct and providing a safe and professional environment at all times."
Lily Allen's publicist told CNN that the artist had no further comment beyond what she said in the podcast.