A Dallas woman who dedicated her life to fighting against domestic violence was beaten to death by her ex-boyfriend, a grand jury indictment revealed on Wednesday.

Nathaniel Mitchell, 34, was accused of fatally beating his on-off girlfriend Donna Alexander, 36, after breaking into her home. He was charged with murder on Tuesday after a grand jury recommended as much in an indictment.

Alexander’s two children later told family they were locked in a room and could hear their mother screaming and glass breaking after Mitchell allegedly broke in through a bedroom window, a local news station reported at the time.

“No matter how much she tried to get away, he always ended up back in her life,” said Lauren Armour, the victim’s sister, adding that Alexander had recently kicked Mitchell out of her home.

In addition to murder, the Tarrant County Grand Jury also indicted Mitchell on charges of burglary with the intent to commit assault, and aggravated assault. If convicted, he faces a maximum sentence of life in prison, police confirmed.

On Sept. 21, police responded to a call around 5 a.m. from staff at Baylor & Scott White Hospital in Grand Prairie, Texas, where Mitchell took Alexander after the attack. The hospital immediately noticed her “severe injuries” and transferred her to Baylor University Medical Center about 45 minutes away, Grand Prairie police officer Mark Beseda told The Daily Beast.

Before transferring them to the next facility, the staff asked Mitchell for details on the incident, as Alexander was unconscious at the time. Because the hospital staff “believed his story was inconsistent with her injuries,” they immediately alerted the authorities.

“Officers met the ambulance at the Dallas hospital and Nathaniel showed up a short time later,” Beseda said. “They interviewed Nathaniel and ended up arresting him at the hospital on outstanding warrants.”

Mitchell initially told police that Alexander fell in the shower, but Tuesday’s indictment revealed that he allegedly hit her “with an unknown object” or “pushed her” causing her to fatally “strike an unknown object.”

He was charged with aggravated assault hours after the incident due to the severity of the injuries, police confirmed, but that charge was later upgraded to murder after Alexander was pronounced dead.

“He used the thing that God gave us all, his hands, that were meant to heal... and he used them as a weapon toward my child,” Alexander’s mother Dalfinne Lassiter told a local news station.

Alexander was the owner of the Anger Room, a facility that allows people to break things as a way to relieve stress in Dallas, Texas. She succumbed to her wounds and died at the hospital three days after the attack.

The Anger Room, which was featured on an episode of Real Housewives of Dallas, was meant to “provide an alternative to seeing a ‘head doctor’ or talking it out when you’re having a bad day,” the website said.

“At the the moment the Anger Room is no longer in business until further notice until we can sort out how to let her legacy live on,” a statement from the companyon Facebook said earlier this month.

Armour couldn’t help but notice the cruel and tragic irony of her sister’s death in light of her life’s work. “Donna’s thing was, instead of people hurting people, why not let it out on objects so a life isn’t lost, to keep people out of jail?” she said.

The inspiration behind the stress-relief facility, Armour explained, was from their rough childhood in the south side of Chicago. “We dealt with violence and homelessness with our mother,” she said. “Our mother’s experienced domestic violence herself.”

But despite her dedication to end domestic violence in Texas, Alexander only told a couple of people about her own relationship troubles, a local news station reported at the time of her death.

“Her very last prayer request was for her assailant,” said Brian Carter, the Associate Pastor at Crossroads Christian Church, told CBSDFW. “His heart was not right and she prayed that his heart would soften.”

Since his arrest, Mitchell has been in custody of the Tarrant County Jail, where he remains until his trial. His bond was set at $250,000, according to jail records.

The case was assigned to Criminal District Court No. 2, and will be handled by district attorney’s Intimate Partner Violence team.