A high school senior faces involuntary manslaughter charges in Massachusetts for urging her boyfriend to commit suicide, according to police.

Michelle Carter, 18, is accused not only of failing to seek help for Conrad Roy III — who, police say, Carter knew intended to commit suicide — but also of texting him during the act and pressuring him to go through with it, according to authorities.

In the more than 1,000 messages between the two, police found numerous texts sent to Roy indicating that Carter was communicating with him until the moments before his death last July.

But there was one message that was particularly chilling, police say. Noting that he was afraid and didn’t want to leave his family, Roy noted that he got out of the truck where he would later be found dead. After texting Carter about his fears, she replied: “Get back in.”

Roy was found in his truck dead of carbon monoxide poisoning the following day, July 13.

“Instead of attempting to assist him or notify his family or school officials, Ms. Carter is alleged to have strongly influenced his decision to take his own life, encouraged him to commit suicide and guided him in his engagement of activities which led to his death,” Gregg Miliote, a spokesman for Bristol County District Attorney Tom Quinn, said in a statement to the Sun Chronicle.

In a report filed in New Bedford Juvenile Court, Fairhaven Police Detective Scott R. Gordon suggested that Carter encouraged Roy to kill himself while simultaneously putting together “a plan to get sympathy from her friends,” according to South Coast Today.

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Gordon alleges that such a plan was evident because late on the night of July 11, two days before her boyfriend was found dead, Carter had “already started explaining (to friends) that it’s her fault that Conrad is dead, even though he was still alive and speaking and texting with her regularly.”

That same day, Carter also texted Roy: “Let me know when you’re gonna do it.”

In the months after Roy’s death, Carter helped raise thousands of dollars for suicide prevention in her dead boyfriend’s name.

But writing to friends after Roy’s body was discovered, police say, Carter appeared to acknowledge that her messages to her boyfriend were intended to encourage him to go through with the suicide.

“[H]is death is my fault like honestly I could have stopped him I was on the phone with him and he got out of the car because it was working and he got scared,” Carter texted a friend Sept. 14, according to the Boston Herald. “I [expletive] told him to get back in … because I knew he would do it all over again the next day and I couldn’t have him live the way he was living anymore I couldn’t do it I wouldn’t let him…”

Carter’s parents say that their daughter, an honor roll student, is being unfairly portrayed as a villain.

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“Our hearts have and remain broken for the Roy family,” her parents said in a statement, according to the Boston Herald. “For everyone that does not know our daughter, she is not the villain the media is portraying her to be.”

They added: “She is a quiet, kind, and sympathetic young girl. She tried immensely to help Mr. Roy in his battle with depression. We know that once all of the facts are released, our daughter will be found innocent.”

Carter was indicted Feb. 6 on charges stemming from Roy’s death. Charging documents, filed in juvenile court because Carter was 17 at the time of the suicide, were obtained last week by local news organizations.

The charges have added a horrifying dimension to an already tragic story, particularly for Roy’s family, which is now reliving the worst moments of his death.

Janice Roy told CBS affiliate WBZ that despite her grandson’s long struggle with depression, she believes he could have been persuaded to not follow through with his suicide plan.

“We were hoping,” she told the stations. “He seemed to be pulling out of it.”

Of hearing about the text messages, she said: “I felt like the blood drained out of me. I don’t believe this, it’s too horrific.”

It’s a dramatic turn of events for Carter, who in the months after Roy’s death mourned him publicly and used his death as a catalyst for activism on suicide prevention.

In messages on Twitter, Carter wrote, “such a beautiful soul gone too soon.” And, “I will never understand why this had to happen.” Carter’s Twitter account has since been deleted and she is prohibited from using social media while charges are pending.

She helped plan a fundraising softball tournament for Roy called “Homers for Conrad.” But even that raised the suspicions of Roy’s friends, who told police that she was “looking for attention” after Roy’s death, according to court documents obtained by the Boston Herald.

Roy’s best friend told Gordon, the detective, that Carter accused him of trying to take “credit” for the fundraiser idea and that her name was added to the fundraiser’s Facebook page because “it bothered her” that she wasn’t listed, according to the Herald.

His friend apparently had no idea that the two were in a relationship.

“He further explained that (Carter) was getting so involved in it, and he was just curious about how she knew Conrad, and Michelle said that they had been dating on and off for 2 years and (he) said at that point that he had never heard of her, so he didn’t know exactly if that was true or not,” Gordon wrote, according to the Herald.

“Carter has a history of being the ‘girl that cried wolf,’ and sometimes (it) was hard to tell if she was being totally truthful,” another friend told police, according to the report.

Carter’s attorney remains confident that the case has no merit and has accused the Bristol County District Attorney’s Office of bias. Quinn, the district attorney, is Roy’s third cousin and has recused himself from the case.

“Everyone in that office knows that they are prosecuting somebody who is alleged to have caused the death of their boss’s cousin,” said Carter’s attorney, Joseph Cataldo, according to the Boston Herald. “I don’t know how you can separate that and have somebody objectively looking at this … as a prosecutor needs to do.”

Carter was released on $2,500 bail and will be tried as an adult.