Nicole Scherzinger is reportedly sick of being portrayed as "unlucky in love".
The singer has been dating Formula One star Lewis Hamilton on and off since 2008.
Despite calling things off last summer, it was rumoured they had reunited this month and that they were engaged.
Lewis put an end to the speculation by tweeting: "Hey all, need to talk about these rumours. I thought I should let you guys know that I haven't proposed to Nicole. (sic)"
"Nicole hates the thought of people seeing her as unlucky in love," a source told British magazine Star.
"She felt humiliated after Lewis publically denied the rumours, because it really has hit home that they haven't moved on or resolved the differences that caused their breakup in the first place.
"Lewis' unwillingness to commit has always been a sticking point and he's now confirmed that marriage still isn't on the cards. Nicole feels so stressed - it's at times like this that she wishes she wasn't famous at all."
It's thought Nicole was the one who initiated the pair's last breakup. The former Pussycat Doll apparently wanted more from the relationship than Lewis.
"She'd grown frustrated that Lewis wasn't keen to move forward and told him she wouldn't wait any longer," an insider previously confided.
"They ended up having a furious row on the phone about his half-hearted 'we might get engaged sometime in the next year' comments.
"Lewis told her that he was in no rush to get married. And for Nicole, this was the final straw. She told him that if he wasn't going to take things to the next level, then she would carry on without him."