To a large extent Independents are unhappy with Washington Grid lock.
And yes, there are independents that no longer have as much faith in Obama and the democrats as they used to. Which shows up in polling data.
If the departing independents were defecting to the GOP, it would be a democratic worry, the problem for the GOP is that they lose independent support even faster.
The other problem is that the GOP does not know what it is and has not defined itself. On one hand, the GOP can't be for the failed stinking turd policies of GWB, yet at this point in time, that seems to be all the GOP knows. And to add to the confusion, the GOP has no platform its defined, and hence the elephant knows nothing but milling around and dragging its feet. In short, the GOP is nothing but a split in to two pieces dead weight and a negative force.
And an independent is largely an independent because they are unhappy with whole dogma of both political parties. The GOP's problem with independents is that will not attract any independents until they define themselves as a positive and not a purely negative force. And when half of the GOP are Palinites and the other half are Cainanites, it gives the GOP a psycho split personality.