"Through not only the marriage, but the music as well, we've created many unforgettable moments," Lavigne wrote on Instagram
Credit: Denise Truscello/Wireimage

Avril Lavigne and Chad Kroeger are separating.

The singer announced their split on Instagram Wednesday, writing:

“It is with [a] heavy heart that Chad and I announce our separation today. Through not only the marriage, but the music as well, we’ve created many unforgettable moments. We are still, and forever will be, the best of friends, and will always care deeply for each other. To all our family, friends and fans, thank you sincerely for the support.”

Lavigne, 30, and Nickelback rocker Kroeger, 40, have been married for two years, having tied the knot in Canada in July 2013.

Within a year of their married life, the couple were dogged by rumors their relationship was on the rocks. And the pair only added fuel to the fire when they started breaking their self-imposed “marriage rules” last year.

“When you have something special, you can’t take it for granted and be careless with it,” Lavigne told PEOPLE in 2013, explaining how she and Kroeger made it work. “We want to give it all the care and love and nurturing that we can.”

The news of their split comes at a time when both singers are on the mend.

In an exclusive PEOPLE cover story in April, Lavigne disclosed her debilitating battle with Lyme disease and, at the time of the interview, shrugged off reports of marital strife, noting Kroeger was “very supportive” during her health scare and road to recovery.

While Lavigne has been on the mend lately, Kroeger has fallen ill himself. After having a cyst removed from his vocal cords, Nickelback canceled the rest of their 2015 tour dates because, per a statement from the band, he “must remain on vocal rest as ordered by doctors for the next six to nine months in order to fully recuperate.”

This is Lavigne’s second marriage. She split from her first husband, Sum 41 frontman Deryck Whibley, in 2009.