Damian Brogan, 47, tormented the woman with sick messages between March 2023 and March 2025.
The victim was left so worried that she rigged up a security camera at her home.
The woman told Glasgow Sheriff Court that she initially got on with Brogan, but this started to change in August 2022.
She said: “I started seeing someone, and he was from Northern Ireland, and he was a Protestant.
“Damian’s family are Catholics from the Republic of Ireland, and he is very much into free Ireland.
“I am not bigoted, and I don’t have hatred for anyone – I have a lot of family members who married into protestants from Northern Ireland.”
When her then partner was going to visit her, she claimed she told Brogan not to “bring up anything” but stated: “It was the first thing he mentioned to him.”
The woman claimed that other people noticed Brogan, of the city’s Shawlands, acting differently around her.
She recalled an occasion when Brogan was driving a vehicle where she and another person were passengers.
The woman stated that Brogan’s driving was “very scary” and the other person asked him to slow down.
The woman told the court that her work was involved in a charity day in Glasgow in 2023.
In the lead up to the event, Brogan sent an email to her which said: “Karma is gonnae get you good if it hasn’t already.”
The woman said: “I was panicking that Damien was going to turn up.
“Bigwigs would be there. I know he said he would go as it would put me in a state of fear.”
In another email, Brogan wrote: “Feel threatened, erratic driving, snidey, pushed over a wee Rangers fan. You have lost it. I’ll be out on my bike so I will be swinging by to say hello.”
In a later message – which had the subject ‘Farm Animal’ – Brogan said: “Oink oink. Tiocfaidh ar la in more ways than one.”
When asked how she felt, the witness replied: “Not great, it felt like he was getting to me.
“Tiocfaidh ar la means our day will come and it’s as if he was warning me my day was coming.”
An email eight month later said: “ROFL, chickens coming home to roost, get it roon ye.”
On January 1 2025, Brogan sent a message which said: “Happy New Smear of pile cream.
“You pathetic lying backstabbing troglodyte.”
The woman said; “This was when emails started to coincide with Celtic and Rangers games coming up. I think Celtic games triggered him.
“I didn’t deserve any of that. It was just because I didn’t want to be friends with him. I was just a single mum.”
Two months later, another email which had the subject ‘Leprachaun’ said: “Karma never forgets and always keeps a receipt, you know that”.
The woman said: “I didn’t know what he was thinking of or what he was going to do. I know things he did to other people – was he going to do that to me?
“I put a security camera in, thinking he was going to turn up to my door.
“The emails were coming through when big Celtic games were on and other things he knew I would be enjoying. He took that away.”
Brogan was found guilty of a stalking charge following a summary trial with no jury.
He was fined £420 and given a three-year non-harassment order, which prohibits his contact with the woman.
