Lindsay Lohan and Matt Nordgren have decided to go their separate ways just one week after their romance became public Credit: Jason Merritt/Getty; Angela Weiss/Getty

Suddenly single! Lindsay Lohan and Matt Nordgren have decided to go their separate ways just one week after Us Weekly and other outlets confirmed they were dating, an insider tells Us.

"Their work schedules and the distance just make dating impossible," the source says of the Canyons actress, 27, and the clean-cut Texan, 30. "He really likes and respects her. He thinks she is back on top, emotionally and physically."

If she is, he may be part of the reason why. Insiders told Us last week that Nordgren -- a former quarterback for the University of Texas and the Philadelphia Eagles -- was a good influence on Lohan, who recently completed a court-ordered stint in rehab.

"He's older, a successful businessman, and he has been a great friend to her," one source told Us. "He's also a Christian and won't drink around her. He's trying to keep her sober and on the straight and narrow. He's really good for her."

As previously reported, the two actually met seven years ago through mutual pals. "We've hung out," Nordgren told the New York Post's Page Six recently. "But I have been a friend trying to support her for many years now." 

That friendship is still intact, the first insider says. "He respects her sobriety and wishes her the absolute best," the source tells Us. "They will remain good friends."