Rihanna is reportedly hoping Chris Brown will respond to her "hints".
The singer and her ex-boyfriend, who assaulted her in 2009, reconciled this year, but broke up shortly after.
Chris suffered a seizure earlier this month, which reportedly left the 25-year-old Barbadian star worrying about his welfare.
Rihanna posted a picture of herself in a taxi online recently, claiming she was asking the driver to be her "shrink".
"As much as she has tried to move on with her life since Chris, Rihanna really does feel there's something missing without him. There are things she told him that she still doesn't feel comfortable telling anyone else," a source told British Star magazine.
"She's secretly hoping Chris will take the hints she is putting out and get in touch."
Chris was given the all-clear after his collapse in a Los Angeles studio and the seizure was put down to stress and exhaustion.
However, this apparently didn't stop Rihanna worrying about the 24-year-old.
"Rihanna and Chris move in different circles now, but she still felt sick with worry when she heard what happened to him," the insider said.
"It reminded her that she is always going to care deeply about him, despite their traumatic past."