The singer said she agreed to take part in a HBO film celebrating 25 years of her classic album Jagged Little Pill.
However, the film, which also addresses the alleged exploitation, "is not the story I agreed to tell," she added.
The director of Jagged has not yet responded to the singer's comments.
In her statement, Morissette noted she had been dealing with post-natal depression at the time.
"I agreed to participate in a piece about the celebration of Jagged Little Pill's 25th anniversary, and was interviewed during a very vulnerable time (while in the midst of my third postpartum depression during lockdown)," the 47-year-old said in a statement.
"I was lulled into a false sense of security and their salacious agenda became apparent immediately upon my seeing the first cut of the film. This is when I knew our visions were in fact painfully diverged.
"This was not the story I agreed to tell," she continued. "I sit here now experiencing the full impact of having trusted someone who did not warrant being trusted."
The Canadian star went on to confirm she has chosen not to attend any promotional events around the movie, firstly because she is currently on tour, and secondly as she believes the film "includes implications and facts that are simply not true".
"While there is beauty and some elements of accuracy in this/my story to be sure - I ultimately won't be supporting someone else's reductive take on a story much too nuanced for them to ever grasp or tell."
On Tuesday, before the new statement was issued, the film's director Alison Klayman told the Washington Post it was "a privilege" to make the film and that she was "really proud of it".
"Hopefully there will be other opportunities in the future for her to come to film events," she said.
The BBC has asked Klayman for further comment in light of Morissette's latest statement.
According to the Washington Post, the film sees the singer open up about being sexually exploited by unnamed people within the music industry at the time - a topic she previously addressed in the lyrics to one of her songs, Hands Clean.
Canada's legal age of consent is 16, although it was 14 when Morissette was a teenager. However, the law says that even if both parties are over the formal age of consent, it should still be considered whether the relationship involved an abuse of power or trust.
"It took me years in therapy to even admit there had been any kind of victimisation on my part," Morissette says in the film.
"I would always say I was consenting, and then I'd be reminded like 'Hey, you were 15, you're not consenting at 15.' Now I'm like, 'Oh yeah, they're all paedophiles. It's all statutory rape."
"I did tell a few people and it kind of fell on deaf ears," she says. "It would usually be a stand-up, walk-out-of-the-room moment."