"I want to thank my family, in particular my mum and dad for helping me through the toughest week of my life. They have been amazing and have now stood by me through thick and thin – I can’t say enough about them – I could not wish for better parents,” he said.
"My brother and I have reconnected and love each other very much - our family has always been our priority."
"The support I have received from so many people in Australia and around the world has also been incredible. I wish I could reply to every single message or well wish I've had, which is impossible at present, as I'm so grateful for each and every one of them."
He revealed he was going to focus on his mental health.
"This is a very private matter that I am going through and I am going to work my way through it," he said.
"I would appreciate it if everyone would allow me and my family to do everything we need to do. I know I have some mental health issues and I am seeking help here in Australia and I will be also going overseas."
The former Olympic swimmer was arrested earlier in the week after witnesses say he was "going off" and stabbing a knife into a chopping block.
He was later released without charge.
The day after he was released from police custody following an incident at his parents’ home, Grant Hackett has claimed his brother, Craig, “beat the sh*t out of me.”
The troubled former swimming champ posted a photo of himself on Instagram revealing a bloodied and bruised face.