Expectations are pretty low for this week's Syria peace talks in Geneva. It will the first time that government and opposition representatives actually meet since the civil war began almost three years ago. But a third major player in the conflict will be missing: the Al-Qaeda-affiliated rebel group that controls much of north-east Syria. Most of its fighters are foreign. Here's the story of one Syrian man who has been forced into exile by the very men he once helped bring into his country.