Miller was handed the suspension for violating the league's substance-abuse policy and will now be subject to up to 10 unannounced drugs tests per month as a result of being in stage three of the NFL drugs program.
Fox has acknowledged that Miller had made mistakes, but insists that the Broncos have plenty of people around to help him get through this tough time.
"He's worked really hard with our strength department, I know he's worked hard in meetings, he's taken and turned in the tests, we test our players every week to see if they're on top of all the game plans," Fox told reporters.
"He's got the support of everybody here. As far as off the field, I can't speak to all of that.
"I think he understands that, you know, he made some errors and there are a lot of people here the help him, his teammates, coaching staff, people in the organization, we'll see where it goes. People in life make mistakes. We'll see where that goes."
Miller has vowed to work hard in order to regain the trust of his teammates.