Like many happily-married couples, Jennair and Mark Gerardot often posted pictures and writings of their love for each other on social media.
My birthday present 24/7. I'm a lucky guy, Mark wrote, uploading a photo of a smiling Jennair.
They'd been together since their college years and with their two rescued golden retrievers, seemed like the perfect family.
They went travelling, and even worked together at the design agency in South Carolina that Mark had started from the ground up.
Eventually, they were both ready for a change. Mark was invited for a job interview at a university in Delaware.
Getting the job, he moved first and Jennair stayed behind for six weeks to lease out the house and pack up their belongings.
Despite their distance, Mark's posts on social media were unwavering.
My wife and golden retriever are the centre of my universe and the reason I get up every morning, he wrote.
Jennair wrote on one online profile that she was a woman who believed that, ...love never fails.
To the outside world, they were a loving, hardworking couple with an enviable relationship.
But behind the smiling photos was a whole other story.
After 25 years of marriage to Jennair, Mark had started a whirlwind affair at work with his new supervisor, Meredith Chapman, 33, a woman who was 15 years his junior.
They had a professional relationship, but also shared details of their personal lives and their respective marriages.
Within a month, Mark was infatuated with Meredith, a smart and successful woman. It took just weeks for him to profess his love for his mistress and she reciprocated.
When he mentioned Meredith during calls to Jennair, she became suspicious it was an affair.
Once she relocated to their new home, she hired a surveillance company to access both Mark and Meredith's phones.
Then, she secretly sewed tiny recording devices into Mark's jackets so she could hear their conversations. Jennair finally confronted him.
"She asked me, 'What is up with you? You're acting different'... 'It's Meredith, isn't it?'" he said during an interview with TV show 20/20.
He initially denied the affair, but Jennair said she had indisputable proof and he eventually came clean.
They agreed to go to marriage counselling to either reconcile or make the separation easier.
But after discovering the listening devices his wife had planted in his clothes, Mark was adamant he wanted to divorce his wife and move on with Meredith. Jennair didn't take it well.
"You don't find me appealing. You don't find me attractive. You don't want me anymore," she told Mark during one phone call.
"You don't even like me. You are miserable. She lights your fire, she makes you feel young. You're excited, it's all fresh. You're getting to know each other and you are in love with her."
He hoped to make the separation as smooth as possible.
Jennair was now living in a new state, with no job, no friends and no husband, so he tried to stay amicable and support her.
Under Delaware law, they had to be apart for six months before they could divorce.
By then, Meredith had split from her husband. She'd scored a new job and was still smitten with Mark.
When she posted a photo to Instagram outside her new uni faculty, friends said they'd never seen her so happy.
Meanwhile, Jennair was hatching a sinister plan.
She bought a .375 calibre revolver and started firearms training. She'd set up a separate credit account and bought location tracking devices, which she'd attached under both Meredith and Mark's cars.
On April 23, 2018, Mark and Jennair had dinner plans to discuss the details of their pending divorce.
Mark was waiting at the restaurant when he received a series of texts.
I'm not coming, go home, Jennair wrote to him, before sending a picture of a condom in a trash can, seemingly at Meredith's house.
You ruined my life. I hope you never find happiness. Goodbye Mark.
Terrified, Mark drove to Meredith's house and peered through the window to find someone lying on the floor.
He called out to neighbours for help and got inside, where he tried to wake Meredith.
A neighbour took over and in a panic, Mark looked around and found another body. He thought he recognised her face.
When emergency services arrived, Mark begged hysterically for people to fix the situation.
"They're gone," someone said, and he became inconsolable, unable to believe it was real.
Over time, through his grief, Mark found out what had happened.
Jennair had covered her blonde hair with a brunette wig and driven to Meredith's house.
No-one was home, so she broke in by smashing the glass on the front porch window. Then, she lay in wait, gun in hand.
As soon as Meredith walked in at 7:05pm, Jennair opened fire, killing her instantly. Then, she turned the gun on herself.
The tight-knit community was rocked by the murder-suicide.
Meredith was a well known and valued member of her community, so the media latched onto the tragedy, selling it as if it was a plot line in a TV drama.
"You had a man that was married that was having an affair with this other woman.
"The wife knew about it, and this was a calculated, planned attack," Superintendent William Colarulo said. "She broke into the house. She was lying in wait, and she shot her as soon as she walked in, then she shot herself."
Meredith's family insisted this wasn't about a 'love triangle'.
"Perhaps the loss of a cherished life can be blamed on a jilted lover, but not one who was unaware her relationship was over, being lied to or led astray. Meredith Chapman did not deserve to die," they said in a statement.
A year after the murder, Mark says he regretted how it played out.
"My regret comes back to breaking her heart and making her feel like she had no other choice..." he said, speaking of Jennair.
"I wish I could take it back."
Today, he still writes private letters to Meredith and drives by her house to help him come to terms with what happened.
"I forgive Jennair for what she did to me…" Mark says. "I have yet to forgive her for what she did to Meredith. She took someone else's life. It's unforgivable."