Avril Lavigne has encouraged her ex-husband to ''stay strong.''

The 'Here's To Never Growing Up' hitmaker - who is married to Nickelback frontman Chad Kroeger - voiced her support for Deryck Whibley on Twitter after he opened up about his battle with alcoholism from his hospital bed.

In a post titled 'Rock Bottom,' the 34-year-old Sum 41 rocker, who has been receiving treatment for a month, wrote: ''The reason I got so sick is from all the hard boozing I've been doing over the years. It finally caught up to me.

''I was drinking hard every day. Until one night. I was sitting at home, poured myself another drink around midnight and was about to watch a movie when all of a sudden I didn't feel so good. I then collapsed to the ground unconscious.''

Deryck panicked when he woke up in an intensive care unit, but is determined to get his life back on track.

He added: ''I had no idea where I was. I was so freaked out. My liver and kidneys collapsed on me. Needless to say it scared me straight. I finally realised I can't drink anymore. If I have one drink the docs say I will die (sic).''

The Canadian musician divorced Avril in 2010 after four years of marriage, but she still supports him.

After reading his post, the 29-year-old beauty tweeted on Saturday night (17.05.14): ''I am so proud of him. He is family to me and always will be. #StayStrongDeryck''