Britney Spears has spoken for the first time since her husband Sam Asghari announced their split, saying she "couldn't take the pain anymore".
Mr Asghari, 29, cited "irreconcilable differences" in a divorce petition filed in Los Angeles on Wednesday.
He asks that spousal support and payment of legal fees be paid by Ms Spears, the documents state.
Ms Spears, 41, said she was "a little shocked" that her six-year relationship with Mr Asghari had come to an end.
Discussing their breakup in an Instagram post, the singer wrote: "I'm not here to explain why because it's honestly nobody's business."
"I've been playing it strong for way too long and my Instagram may seem perfect but it's far from reality and I think we all know that," she added.
"I would love to show my emotions and tears on how I really feel but for some reason I've always had to hide my weaknesses."
Ms Spears said she would be "as strong as I can" and she was "actually doing pretty damn good".