Los Angeles, Jan 13 : Singer-songwriter Bruno Mars' long-term relationship is reportedly "on the rocks." The 38-year-old singer has been dating model Jessica Caban for 13 years, having started their relationship back in 2011. The 41-year-old is said to have spent Christmas and New Years away from Bruno, amid the reports about their shaky relationship, reports Mirror.co.uk. Sources told The Sun: "Bruno Mars and Jessica barely spend time together anymore ' it is really sad. They are living separate lives so it doesn't bode well for their relationship. It feels like things are fizzling out between them.' "They have so much history together but we aren't sure whether they will be able to save things this time," an insider explained. As per Mirror.co.uk, Bruno Mars is currently performing in Tokyo but is set to return to the US to perform in Los Angeles. The couple started dating when the 'Just The Way You Are' hitmaker saw Jessica in an NYC restaurant and decided to introduce himself. They tend to keep off social media and were said to be living in Hollywood Hills with their dog Geronimo. Bruno usually stays quiet about his romance with the model, but told Rolling Stone that he was "happy" with her, but seemingly had no plans to propose. When asked if he'd get down on one knee, he seemed taken aback and said: "Jesus! She's my best friend. My rock. What's wrong with that? We're just happy'. /IANS