How was Washington able to hold together his army at Valley Forge?

He barely did. In fact, his army was ready to revolt against him. Times were hard and tough. Luckily Washington was an effective leader and general. Not the exact historical way of putting it, but it's accurate enough to be correct on a test. Sorry, I haven't read up on Valley Forge in awhile. I can tell you no battle (or at least any of significance) happened here.