Mod Sun is focusing on the future in the wake of his break up with Avril Lavigne. Just a week after the news broke of their split, the former couple's engagement of 10 months officially ended and the musician is now reflecting on his unexpected life change.

In an Instagram post on Tuesday, Mod Sun (real name Derek Smith) wrote a heartfelt message expressing his complex emotions since their parting. "In 1 week my entire life completely changed...I just know there's a plan for it all," he wrote. "I'll keep my head up + always listen to my heart, even when it feels broken."

According to People magazine, the pop-punk rocker and Lavigne, 38, had been on-again, off-again for the past two months and ended things amicably. A rep for Mod Sun also clarified that he was blindsided by the