Reports from Aleppo civilians, and journalists who are / have been in Syria and Aleppo are that there are none of the original "rebels" left - that they've all either left, or joined the Syrian army. And all that's still fighting against the Syrian nation are ISIS.
There are also reports from civilians of the "rebels" executing anyone suspected of sympathizing with or supporting the Syrian government, of people who try to escape "rebel"-held regions, and even people who are merely asking for food because they're starving in the "rebel"-held regions..