Rihanna shows off her six pack while smoking in a photo posted to Instagram by friend Melissa Forde. Photo: Instagram

The singer definitely deserved some relaxation time after a crazed fan chucked a bottle at her as she left the after-party of her fashion show last Saturday night. Rihanna was left with a bloodied knee and was shaken up by the incident.

While Rihanna was relaxing, her boyfriend Chris Brown was nowhere in sight. Brown was in Houston headlining the NBA All Star Weekend. Also in town was Brown's ex-girlfriend Karreuche Tran who raised eyebrows when she posted a picture on Instagram of an ornate ceiling with the caption: "Gnight." The ceiling is rumoured to be that of the mansion that Brown and his friends rented over the weekend. Tran promptly deleted the photo.

Rihanna pulls at her bikini straps suggestively. Photo: Instagram

Rihanna and Chris Brown only just went public with their relationship at the Grammy's, but there are already rumours that the relationship is showing cracks.

However, Rihanna's putting the whole thing behind her with this girly get-away. RiRi and her pals are actually all away for her birthday. The singer turns 25 today and looks set to be partying the night away. Let's hope that Chris Brown WON'T be on the guest list.

GALLERY: RIHANNA'S SEXIEST PICS. PHOTO: TWITTER