Her romance with Paul was her first since her divorce from Simon Konecki in March 2021.
The singer shocked fans by pulling the opening shows of her much-anticipated new Las Vegas residency just one day before it was due to open.
Adele, whose fourth album 30 is riding high in the charts worldwide, made the tearful announcement via Instagram, just over 24 hours before the first show was due to take place.
She explained that the residency, first announced last November, "wasn't ready" due to Covid and other production delays.
"I'm so sorry, but my show ain't ready. We've tried absolutely everything that we can to pull it together and have it ready in time for you, but we've been absolutely destroyed by delivery delays and Covid," she began, her voice shaking.
"Half my crew, half my team are down with Covid – still are. It's been impossible to finish the show. I can't give you what I have right now, and I'm gutted," she continued.
"I'm sorry it's so last-minute. We've been awake for over 30 hours now trying to figure it out and ... we've run out of time. I'm so upset and I'm really embarrassed and I'm so sorry to everyone that's travelled again.
"I'm really, really sorry. We're on it, we're going to reschedule all of the dates, and I'm going to finish my show and get it to where it's supposed to be.
"It's been impossible. We've been up against so much and it just ain't ready," she continued, apologising repeatedly once more.
A source previously claimed the star launched into a furious rant over a swimming pool stunt planned for the big-money shows.
The British star was supposed to stand in the middle of a pool while belting out her hits – but likened the final design to an "old pond" and refused.