Michelle Carter, the Massachusetts woman sent to jail for encouraging her boyfriend to take his own life, was denied early release, the state's parole board announced Friday. She has served seven months of a 15-month sentence for her role in the 2014 death of Conrad Roy.

Carter was convicted of involuntary manslaughter in 2017. Roy, 18, took his life after Carter, then 17, told him over the phone and via text to get into his carbon monoxide-filled truck.

"The [board] is troubled that Ms. Carter not only encouraged Mr. Conrad to take his own life, she actively prevented others from intervening in his suicide," the Massachusetts Parole Board said in its decision, according to CBS Boston. "Ms. Carter's self-serving statements and behavior, leading up to and after his suicide, appear to be irrational and lacked sincerity."

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The board said Carter's release was "not compatible" with the best interests of society and that her appeal failed to justify her "lack of empathy" for the crime.

Carter's attorneys have argued her texts were constitutionally protected free speech. The state Supreme Judicial Court disagreed, upholding her conviction in February.

Carter's lawyers appealed to the U.S. Supreme Court in July, but the court has not yet decided whether it will take up the case.

Daniel Marx, who argued the case before the Supreme Judicial Court, said in February that the court's ruling "stretches the law to assign blame for a tragedy that was not a crime."

Carter remained free until her state appeals were exhausted. She began serving her sentence in February.

The case has sparked legislative proposals to criminalize suicide coercion. Massachusetts lawmakers have proposed "Conrad's Law," which would make convincing or manipulating someone into taking their life a crime punishable by up to five years in jail.

Carter and Roy met in 2012 while vacationing in Florida. They lived an hour apart in Massachusetts, communicating almost exclusively via texts, online and by phone. Both struggled with depression, and Roy had previously tried to kill himself.

Roy detailed his mental health struggles to Carter many times leading up to his death on July 12, 2014. She sent him dozens of texts from more than 30 miles away encouraging him to kill himself and "get back in" his truck, despite his apprehensions.

"You keep pushing it off and say you'll do it but u never do. It's always gonna be that way if u don't take action," Carter texted him on the day he died.

Two months after his death, Carter sent a text to a friend saying, "It's my fault. I could have stopped him but I told him to get back in the car."

In a June 2017 interview with "48 Hours," Roy's mother, Lynn Roy, said she doesn't believe Carter "has a conscience."

"I think she needs to be held responsible for her actions 'cause she knew exactly what she was doing and what she said," Roy told "48 Hours" correspondent Erin Moriarty.

If you or someone you know might be at risk of suicide, there is help. Call the National Suicide Prevention Lifeline at 1-800-273-8255, text a crisis counselor at 741741 or visit suicidepreventionlifeline.org.