The reality of missing the regular-season opener and facing the unknown hit home for Frederick, who spoke Thursday to the Dallas media for the first time since his diagnosis.
"It's difficult for me personally," Frederick said, via Todd Archer of ESPN. "For a lot of guys in this locker room, you try to push through things. When you're injured, you try and get past it.
"This is something I can't just will my way through. It's a matter of the nerves not conducting properly and not working correctly. It's going to require some patience and some great work from our rehab staff and our strength staff to be able to just continue push forward and take what my body gives me so I can continue to improve as those things come back and then I hopefully I can take that bigger jump."
Frederick, who hasn't missed a game in five straight seasons, dealt with shoulder and neck issues during training camp, and the Cowboys initially believed the Pro Bowl center was suffering from stingers.
Further medical evaluations, however, led to the diagnosis of Guillain-Barre syndrome, an autoimmune disease, and it changed everything for Frederick.
"I was very relieved to finally have an idea of what it was that was going on, because I was having some weird symptoms," Frederick said, via ESPN. "All of a sudden I was really weak.
"After the diagnosis, they tell you what could happen in the future if you don't get treated. I got treatment and things started to improve. That helped relieve some of that uneasiness there. It's hard looking forward not knowing what's coming as far as a recovery standpoint, when I can come back, but knowing that I will get back to 100 percent at some point is certainly relieving."
Backup center Joe Looney projects to start at center while Frederick continues the recovery process.
For his part, Frederick will concentrate on getting better with a view to return to action.
"Right now my focus is getting back to being here and being able to play again," Frederick said, via ESPN. "It's a matter of time for that to happen, and unfortunately, I don't know what that time is. I think as long as I continue to keep my eyes forward and continue to work toward that, we're going to be in good shape."