Rihanna is apparently wondering if she can ever "just be happy" with Chris Brown.
The music stars rekindled their romance last year, after they originally split in 2009 when Chris assaulted Rihanna. Although they have both discussed their feelings for each other in public and marriage rumours have been circulating, the romance still seems to be rocky and it's not clear whether they are currently an item.
Rihanna said she "didn't understand" love while on stage this week and later posted a photograph online of her in a car with Chris.
According to insiders, Rihanna is finding the tempestuous nature of their relationship difficult to handle and wishes things were easier.
"Sometimes Rihanna feels like they can never just be happy together," a source told British magazine Closer.
In an interview at the end of last month, Chris seemingly confirmed he was no longer dating the Barbadian singer. However, last week he hinted they are together and discussed how he deals with his jealously while she is on tour.
Chris has since been accused of getting friendly with a waitress in New York City, while Rihanna was spotted flirting with her male companion at a basketball game in Los Angeles.
To further complicate matters it has been claimed the stars are planning to wed in Barbados this summer.
It has been suggested that Chris and Rihanna veer from spending every moment together and feeling loved-up, to ignoring each other and spending time with other people.
"Chris and Rihanna are volatile and swing from marriage talk to split talk in the same day," the source added. "They're so intense, but have issues with jealousy. They go from sending 100 texts in 24 hours to not talking for two days."