Hayden Panettiere‘s ex Brian Hickersonsays reading about his abusive relationship in her upcoming memoir was brutal … but he also thinks alleged abusers need to hear stories like his the most.

Hickerson spoke with TMZ’s CharlieNeff ahead of the release of Hayden’s memoir, “This Is Me: A Reckoning” … and admitted there was one particularly dark moment from their relationship he requested her to leave out of the book — but it made the final cut anyway.

According to Brian, the passage details a drunken incident where he allegedly threatened to throw a phone at Hayden. He recalled telling her, “I’ll give you 10 seconds to run as fast as you can before I throw it at you.”

Brian admitted to Charlie, “Who wants to read something about themselves like that?” … before adding, “I did it. I did it.”

The ex-couple dated on and off from 2018 to 2022 … and their relationship exploded into public legal drama … with Brian arrested multiple times over alleged domestic violence incidents involving Hayden. He pleaded no contest to felony charges, was sentenced to jail time and probation, and was hit with a five-year restraining order requiring him to stay away from her.

Brian also pushed the conversation beyond survivors … saying people accused of abuse should also be forced to confront these stories head-on. He believes domestic violence education comes too late in life … adding he was never taught what abuse actually looked like growing up.

And in a striking moment of self-awareness, Hickerson suggested Hayden’s memoir could end up serving as a warning manual for the very kind of person he became … proof that sometimes, it really does take one to know one.