BARNSTABLE, Mass. -- The Cape Cod doctor who shot and killed her husband will not be charged, Cape and Islands District Attorney Michael O’Keefe said Friday.

O'Keefe said the grand jury refused to indict Dr. Ann Marie Gryboski, who police said shot her husband, Patrick Lancaster, 50.

“Dr. Gryboski was the recipient of both psychological and physical abuse by her husband for over 20 years,” O’Keefe said in a press release. “In the early years of this abuse, he threatened her with harm to herself and their children as well as any police who might respond were she to call police.”

Gryboski claimed she shot her husband during an argument he was having with their son.

When Gryboski was arraigned for murder in April, she had noticeable bruises on her face. She was released on $50,000 bail after O'Keefe cited “mitigating circumstances.”

Defense attorney Kevin Reddington did not immediately return calls seeking comment Friday.

But in a statement released by Robert Galibois, attorney for Gryboski's son Chris, Reddington said he and Gryboski were pleased that grand jurors recognized that she acted in defense of herself and her son, according to the Cape Cod Times.

"This has been a very trying time for the doctor and her family and we hope that this unfortunate case will now be put behind her and she can get back to work with her patients and the job she loves," Reddington said in the statement.

"Chris is immeasurably relieved that the court process is over," Galibois said on behalf of his client. "He is grateful for the overwhelming support from family and friends during this difficult time."

Reddington had said in court that the case was "pure and simple self-defense."

"The bruises speak volumes about what happened," Reddington has said. "She did what she had to do to protect herself and her children."

Gryboski told police that the night before the killing, her husband had repeatedly punched her as she drove with their 2-year-old grandson in the back seat.

When her husband came toward her on that Sunday, she fired two shots, hitting him in the torso, according to prosecutors.

"She went to him, cradled his body and said 'I didn't want it to end like this, I hope you find peace,'" O'Keefe said in his Friday statement.

Gryboski had been practicing medicine in Yarmouth, but suspended her practice after her arrest.