A woman who said she strangled her 18-year-old daughter because she "pushed my last button" pleaded guilty Tuesday to first-degree manslaughter.

Her husband, who discovered the body, wept during the court session.

Stacy Pagli, 38, had been charged with murder in the Feb. 22 killing of her daughter Marissa at Manhattanville College in Purchase.

But her lawyer, Allan Focarile, claimed Pagli was under "extreme emotional duress" at the time of the killing. Her mental state was the focus of pretrial hearings, and psychiatrists for both sides eventually agreed.

In exchange for her guilty plea, Pagli is to be sentenced to 20 years in prison. Sentencing was set for April 5.

Marissa Pagli, a Manhattanville freshman, was found dead in the family's on-campus apartment. Her father, John Pagli, was a maintenance supervisor at the college.

He found his daughter's body — and his wife lying nearby. The Westchester district attorney's office said that after the killing, Stacy Pagli tried to commit suicide by cutting her left wrist and hanging herself on a doorknob.

While in jail, she tried killing herself by tying socks around her neck, prosecutors said.

According to police accounts of Pagli's statements after the killing, the mother said her daughter was "disrespectful all the time." She said she told her daughter, "This will be the last time you speak to me like that," the documents say.

When police asked what prompted Marissa to be disrespectful, her mother said, "I asked her where she was going," the police account says.

Pagli also expressed regret, saying, "I wish I could take it back, but I can't. I can't make it better," according to the police account.

She said she killed her daughter and tried to kill herself because they were "too much baggage" for her husband, the papers say.