Molly-Mae Hague confronted Tommy Fury about cheating allegations as far back as three years ago, sources have claimed.
According to insiders, Molly-Mae, 25, grew suspicious during Tommy's 2021 boxing training camp in Las Vegas with his brother, Tyson Fury.
The concerns allegedly arose when Tommy, also 25, began ignoring her calls and messages while he was away.
A source told The Sun: 'He was acting weird out there, not answering his phone or messages.
'When he came back, something wasn't right. Molly asked him if he had cheated. He denied it.
'She had no proof so had to leave it. But she was worried something had happened.'
Molly-Mae's representative has declined to comment and MailOnline have contacted Tommy's representatives for comment.
Molly-Mae, announced her unexpected breakup with Tommy, 25, earlier this week after five years together.
In a heartfelt statement on Instagram, she wrote: 'Never in a million years did I ever think I'd have to write this. After five years of being together, I never imagined our story would end, especially not this way.'
Friends have come forward saying the star is 'crushed' as she believed she could 'trust Tommy completely.'
According to reports close to the couple, tensions between Molly-Mae and Tommy escalated at their £4 million Cheshire home after she was informed he had allegedly cheated with a Danish woman he met in Macedonia.
And it told her 'all she needed to know' when he didn't deny it after she point blank asked him whether it was true, one pal told The Sun.
But her 'distraught' boxer ex Tommy insists the claims are 'false' and is said to be 'horrified' by the allegations.
A heartbroken Molly-Mae has been left 'reeling' after kicking Tommy out of their lavish mansion to bring an end to their five year romance.
One of her friends said Molly-Mae thinks the Danish woman 'could be the tip of the iceberg' as she believes 'he has done the dirty before'.
Tommy, who Molly-Mae shares baby Bambi with, released his own statement and said: 'I am heartbroken to share that Molly and I have decided to end our relationship.'
Molly-Mae is reportedly bracing for more women to come forward with claims of affairs involving Tommy, and she is leaning on her close friends for support during this difficult time.