The seizure-prone Staten Island woman who had been charged with fatally mowing down two Park Slope kids in a crosswalk left behind a suicide note saying she couldn’t “do this anymore,” law enforcement sources told The Post on Wednesday.

Dorothy Bruns, 45, was found dead on her bed inside her Concord home by a friend late Tuesday afternoon – with numerous bottles of prescription pills to treat high cholesterol, high blood pressure, seizures, heart disease and depression close by. The small, handwritten note was also nearby, sources said.

It said in part: “I’m sorry, I can’t do this anymore,” according to a police source.

The message also said “do not resuscitate,” another source said, adding that the note gave a friend of Bruns power of attorney.

The pal who made the discovery went to check on Bruns after not hearing from her for a couple of days, a police source said.

Bruns suffered from multiple sclerosis and was prone to seizures.

Prior to the horrific March 5 car crash that killed Joshua Lew, 1, and 4-year-old Abigail Blumenstein, Bruns had been instructed not to drive.

The young children were crossing the busy Brooklyn intersection of Ninth Street and Fifth Avenue with their pal moms, Tony Award-winning actress Ruthie Ann Miles, the mother of Abigail, and Lauren Lew, the mom of Joshua, when Bruns struck all four of them and another person with her Volvo.

The Broadway actress, who won a Tony Award in 2015 for her role in “The King and I,” was pregnant at the time of the crash and later lost her unborn baby.

Bruns was ultimately hit with a 10-count indictment on charges of manslaughter, criminally negligent homicide, reckless endangerment, assault, and reckless driving related to the crash.

She faced up to 15 years in prison.

NYPD Chief of Detectives refused to comment on the contents of Bruns’ suicide note at an unrelated press briefing Wednesday and would only say: “There was a suicide note recovered at the scene as well as evidence of prescription pills, and beyond that I’ll defer to the [Medical Examiner] to conclude the investigation.”

Mayor Bill de Blasio, who once lashed out on Bruns stating she should “never have been allowed to be driving a car,” reacted to Bruns’ death Wednesday, saying “Any time someone takes their own life it’s profoundly sad. And obviously, all we have focused on in terms of mental health is getting people the help they need and getting people to come forward with their problems, so that we can avert tragedies like this.”

“That’s the reality across the board. This is just an extremely painful case from moment one and I wish that none of this had come to pass,” Hizzoner said. “But what’s abundantly clear at the same time is that we have to change our laws so that we don’t have any more tragedies like the one she was originally involved in with those who lost their lives.”

Additional reporting by Tina Moore and Cedar Attanasio