The Snow Patrol band member told MailOnline.com that the American actress “hasn’t got a clue” about what he is saying.
He explained how Covid lockdowns were “tough” as the couple were forced to spend time apart, with him in the UK and her back home in the USA.
Speaking about his “transatlantic” accent, the rocker and record producer joked: “Well my partner is American and she hasn’t understood a word I’ve said in eight years. She hasn’t got a clue!”
The couple began dating in 2013, after being introduced by mutual friends. They announced their engagement in June 2014 but the wedding was called off in 2015.
However, they rekindled their relationship the following year and the remain together.
McDaid lives in London and divides his time between the UK and the US, where Cox lives.
They have been spotted in Derry in the past where they took the time to pose for selfies with fans.
At the height of the pandemic, the couple also sent a Christmas message thanking frontline workers at the Rath Mor community services and retail hub in Derry’s Creggan area.
Johnny said: “We were apart as many people were apart from their families and loved ones, but we were able to stay as connected as we could and both of us dived into being creative.
“She made her show and a new product line, and I made Bad Habits with Ed [Sheeran], so we were able to stay really productive even if it was tough being apart – and it was tough, but we don’t have the toughest lives in the world – we’re so lucky.”
Hollywood actress Courteney quipped that they wouldn’t be able to afford Ed Sheeran at their wedding.
She previously paid tribute to her long-term partner as they celebrated eight years of dating by sharing past and present photos on Instagram.
“Eight years later… I asked him to come up with a caption and he fell asleep. Still got it. Happy Anniversary xoxo,” the Friends star captioned the post.
In 2018, Courteney and Johnny were spotted house-hunting in his native Derry.