For Austin Tice's parents, desperation, and hope

The search for an American kidnapped in Syria is taking on new urgency today.

Austin Tice, 33, vanished two years ago. He was working as a freelance journalist for the Washington Post and other news outlets, including CBS News. Tice's parents haven't spoken in public since American reporters James Foley and Steven Sotloff were killed last month by ISIS, CBS News correspondent Clarissa Ward reports.

"I do not accept that he is missing. I live in a place where he is coming home," Tice's mother Debra told CBS News. She said she doesn't have to try to sustain optimism; "I don't have to sustain it. It's the most beautiful, miraculous gift that God is giving me, every single day. I do not have to keep hope alive. It simply, it encases me."

For Marc and Debra Tice, the last two years have been agony, waiting for news of their eldest son, Austin.

An Eagle Scout, captain in the Marine Corp and fearless journalist, Austin was taken outside Damascus in August 2012.

A chilling video, released weeks after his capture, has been the only sign of him since.

When Debra saw the video, she "went into physical shock."

But nothing could have prepared the Tices for the horror of the executions of Foley and Sotloff.

"Mark came downstairs again, with that look again, and that white face and, you know, that 'I need to tell you something and I can't speak,' you know, and I'm just begging him, 'What? What is it? What is it? What is it?'" Debra recalled, "I mean, it was just such a gut punch, because we had such hope that that would never happen to an American journalist."

Unlike Foley and Sotloff, Austin is not believed to be held by ISIS, and there has been no demand for money, but the Tices are conflicted about the U.S.'s strict policy on paying ransoms.

"If an American citizen is held hostage overseas, you are discouraged and disparaged if you even consider paying a reward for a precious human child, because you don't know where that reward money's gonna go," Debra said. "You know, we're just a mom and dad. We just want our child back, and we wanna do whatever it takes."

One small comfort for the family has been the massive outpouring of support.

"We got an email from a girl that worked at the same restaurant in Georgetown that Austin worked at," Marc said, struggling to contain his emotion, "and she said, 'You know, I was walking home at night by myself, and Austin noticed that. And so he started walking me home every night.' You know... it was just a small thing, but you know, he cared."

Perhaps nobody knows that better than Austin's six younger siblings.

"Oh, it's been hard," Debra said. "I think all of them, to a certain extent, feel like their parents have been captive for two years, as well. Because in the same way that we can't talk to Austin, our kids can't really have full access to us in the way that they did, before this chunk of our heart was just locked away from us."

"I mean, it's, it will always be part of our lives," Marc said. "When Austin comes home, it'll still, we'll all be changed. Certainly he'll be changed."

"One thing I feel sure of, when Austin comes home," added Debra, "we will walk that path."