It’s been a tough year for Paula Patton since her split from husband Robin Thicke, and the 39-year-old model admitted to Robin Roberts on today’s Good Morning America that it hasn’t been easy.

“I mean, the honest truth is, it has been challenging,”; said Paula, who met the “Blurred Lines”; singer when they were both teenagers. “But it’s been a year of growth … learning about all new things. I’ve come out of it stronger… I feel like everything happens for a reason. And then you have to move on and grow from there.”;

As she explains, keeping a positive attitude has been key: “It’s easy to dwell on the negative [but] usually the positive in your life outweighs that. And you have to just be thankful for what you have right now.”;

And what’s happening with Paula right now? She’s just entered into a collaboration with top fashion designer Ellen Tracy for a new clothing line.

“It was kind of an amazing blessing,”; she said. “Ellen Tracy came to me and said, “Would you like to be our brand ambassador?’ And I looked at the clothing and — amazing. It’s really well made, classic clothing that’s affordable. But what I liked about it was that you could, like, add your own twist to it … you can make it as edgy or quirky as you want and add your personality to it.”;

Paula started dating Robin in 1993, and the couple married in 2005. Paula filed for divorce in October, and is seeking full custody of their four-year-old son, Julian.