The blonde beauty is said to have called time on her relationship with Bryan because of his jealousy of her relationship with ex-husband Nick Cannon and his lavish spending sprees.
The ‘We Belong Together’ hitmaker has remained on good terms with Nick since their divorce in 2016, largely for the benefit of their six-year-old twins Moroccan and Monroe.
But Bryan has responded to Mariah’s behaviour – which has reportedly included going to parties with Nick – by flirting and coming onto other women in sight of the singer.
The situation came to a head at the Kids’ Choice Awards in March, when Mariah and Nick took the twins to the ceremony in Los Angeles.
Bryan felt “disrespected” by the situation and, according to TMZ, he even demanded Mariah come home during the event.
Mariah, on the other hand, reportedly grew tired of having to foot the bill for Bryan’s expensive taste in jewellery, while she also suspected he may have been using her to become famous in his own right.
Mariah started dating Bryan shortly after her relationship with Australian billionaire James Packer collapsed in October 2016.
But the American star previously rubbished suggestions she got too close to Bryan too quickly after splitting from James.
The two-time divorcee – who got engaged to James in January last year – said: “I don’t think we’re being public in a way that my relationships have been public before. I really don’t.
“To me, the best thing of this is to keep it a little more private. But I’m not going to not go places with him and enjoy our lives because everybody thinks, ‘Oh, it’s too soon!’ kind of thing.”