The two posed for photos in their glamorous gowns at the star-studded gala.
The one-time child stars showed off their mature styles with Lovato looking lovely in lilac while Gomez opted for classic black.
That wasn’t easy on them.' It was added that while the pinup made an effort to see the Starboy singer while he as touring, it was not enough.
'It’s been hard for them to come to the realization that this is the direction things were heading, but it’s been hard for months.'It may have been hard for him to see Gomez kissing her co-star Timothée Chalamet several times as she filmed A Rainy Day In New York.
However, the former Disney starlet's romance with rapper The Weeknd is still going strong and he was 'fully aware' that his fellow Canadian was seeing his girlfriend.
The hitmaker - real name Abel Tesfaye - is currently on tour.
Selena and The Weeknd made their public debut as a couple at the Met Gala in May.
He has been supportive of her during her kidney transplant and recovery.
She was last seen with him at his September 16 concert in Philadelphia.
In the image of Justin and Selena, the two stars are seen sitting opposite each other, Justin's head covered in a white hooded sweatshirt.
The news broke on Monday morning by People magazine that claimed the two had been having trouble for 'months' because of their difficult schedules - while he has been on tour, she was filming a Woody Allen movie A Rainy Day In New York in NYC.