"The most important thing is to stay strong mentally, even if these are very difficult times," Parker says in an interview – his first since his split – with France's Le Parisien newspaper. "I've take refuge in basketball because that's what I've done best since my youth."
Parker, 28, whose San Antonio Spurs are on a winning streak, tells the newspaper he's trying to "make sense of things" but that his teammates are standing by him and keeping him strong.
The athlete says he appreciates the "support of [my] teammates, coaches and San Antonio." Equally important, he says, "has been my family. My whole family has been around me through this."
Parker, who met up for an amicable lunch with Longoria in L.A. in early December, says he's been avoiding reading anything written about his marriage, and a source tells PEOPLE the NBA star has been noticeably affected by his split. "He has changed," the source says. "He's extremely guarded when he talks about it."
Mostly, Parker says, he's trying to keep a level head and focus on his sport.
"You have to know how to keep things in perspective," he tells Le Parisien. "I am, first of all, a basketball player. I've done this for so very long … For me, it's been essential to be successful on the court."