Till death do us part indeed!

Nearly a year-and-a-half after experiencing organ failure, Avril Lavigne's ex, Sum 41 frontman Deryck Whibley, married model Ariana Cooper on Sunday in LA.

"It was a chill and intimate ceremony," a source tells People magazine. "They had a violin play at the ceremony and the music was mellow, not typical rock that Deryck's band plays, which was surprising."

The couple read their vows under a flower-adorned altar at the Hotel Bel Air, and Ariana stunned in a strapless, beaded ball gown accessorized with white converse sneakers.

The bride stood by the musician's side through his April 2014 hospitalization, which doctors say was the result of serious alcohol abuse. Now sober, the newlyweds celebrated their big day with glasses of apple cider.

Earlier this year, Deryck told Vice that he was "feeling better than I've ever felt," adding, "There are so many exciting things now. So many things are new for me. I'd never done anything sober … Now there's this whole world out there and things I'm realizing I've never done."

Congrats to the happy duo!