"For me it was good to grow up and grow out of that whole situation and that's what I have been doing for the past year, growing up and out of the limelight and making music," Williams told the Herald.
He wrote his song You Got Me, which went to No 1 on the New Zealand charts, about Ms Brown and she starred in the video clip.
The pair are now on amicable terms and jointly parent their two-year-old son, Ryder.
Williams has rekindled his relationship with his high school sweetheart, Renee Marriot, who his new song is about.
"[Brown] is a great mother and [our relationship] is just about our son, so we are in a good spot at the moment as far as being a mother and a father. We are older now, we're mature adults."
When the Herald interviewed Williams - real name Joshua - in 2011 in his small flat in Massey, he said he was too afraid to step out of his house.
But this week, Williams told the paper that alcohol and violence counselling and the support of his loved ones - including Ms Marriot - helped him through the difficult time.
"She's been the light to my darkness, she pulled me out of that place where I was at.
"But another way I am out of that is I have surrounded myself in my close family and my close friends and they've really helped me."
Intensive therapy and counselling meant an end to binge-drinking, and he is in talks with domestic violence campaign organisers to help promote their messages.
During his hiatus in New Zealand, he was busy overseas - he released 20-track album Young Love Special Edition in Japan and visited Australia, Papua New Guinea and Samoa.
"I've been drowning myself in my own creativity - I have been so busy writing and travelling around."
He said his new song was about finding true love: "It's about the thoughts and feelings before you've found the one ... when you've found that one you'll never let them go because it's destiny.
"I've found my one and I am happy where I am," he said.
"I want people to know that whatever you go through in life, there are hard times you feel like you're hitting a brick wall or some speed bumps, but I encourage them to keep chasing that dream, don't stop."