The Baggage Claim star cited irreconcilable differences in her filing, and asked for joint legal and physical custody of their son, Julian Fuego Thicke, 4.
The estranged couple first announced their separation nearly nine months ago, in February, through a joint statement. "We will always love each other and be best friends," the two said at the time. "However, we have mutually decided to separate at this time."
The high school sweethearts first met at an 18-and-under nightclub in Los Angeles when she was just 15 and he was 14. The two were married in June 2005. "We've known each other since we were teenagers," Patton told the June 2014 issue of Vanity Fair. "All I can tell you is there's a deep love there -- always was, and always will be."
During an April deposition, Thicke, 37, gave insight as to why Patton, 38, left him, saying that he was under the influence of either drugs or alcohol for a large part of 2013.
Thicke recalled his routine while promoting the album Blurred Lines, saying, "Every day I woke up, I would take a Vicodin to start the day and then I would fill up a water bottle with vodka and drink it before and during my interviews," he said. "I don't recall many things that I said. In fact, I was quite surprised when I read them back sometimes."
In the same deposition, Thicke adds that he doesn't consider himself to be an "honest person."
"That's why I'm separated," said Thicke. "I told my wife the truth. That's why she left me."
All this year, Thicke has been attempting to win his wife back. Going beyond just telling his concertgoers that he wants to reconcile with Patton, the singer also titled his 2014 album Paula after his estranged wife. "I want everybody here to know: I'm trying to get my girl back," he candidly told the audience at his show in Fairfax, Virginia in February, before dedicating his hit "Lost Without U" to her. "She's a good woman."