The sadistic South Carolina woman who killed her two kids and her estranged husband’s girlfriend before turning the gun on herself left a series of bitter suicide notes behind, blaming her hubby for her actions — and wishing him a lifetime of torment.

“You have caused me more pain that I’ve ever been in in my life. You have caused my children pain. I hope you rot one day for what you have done to me and my kids … I hope you live with pain and shame and guilt for the rest of your life,” killer Jessica Edens wrote to her husband, Ben, according to the Greenville News.

Jessica, 36, was locked in a nasty custody dispute with Ben over her 5- and 9-year-old kids when she went on the spree. Ben had been cheating on her with Meredith Rahme, 28, for about a year, Jessica told cops in the days before the bloodshed.

She blasted rival Rahme while the woman sat in the driver’s seat of her car in a Greenville parking garage around 5 p.m. July 13.

The sicko then called her husband to gloat.

“Everyone you love is gone. Do you hear me? I’m about to be gone too,” she said, according to the Greenville News.

Two hours later, authorities discovered Jessica and her two young children inside her locked-and-running SUV at a garage several miles from where Rahme was killed. Each of the three had a single gunshot wound to the head. A .40-caliber handgun stolen from Jessica’s parents was also recovered.

The bitter note to the husband was found inside the SUV along with two other handwritten notes: one addressed to her parents and sister and the other titled “Last Will and Testament.”

“I am so sorry for the pain I am causing all of you. You’ve all always been there for me and I love you all so much. I know what I have done is selfish, but I cannot live with this pain any longer,” the letter to her family reportedly read.

“I just cannot handle it. It is too much. It hurts too much. I will no longer be in pain and my children will no longer hurt either. I am so so sorry. I love you all.”

The notes were released by the Pickens County Sheriff’s Office in response to a Freedom of Information request filed by the Greenville News.