I make and eat tortillas often and always have the problem of keeping them just fresh enough to fold into burritos without breaking them. Whether you buy or make your tortillas here's a tip for keeping them soft:
Take your stack of tortillas and store them in a Ziplock with a piece of wax paper between each tortilla. Freeze them like this. Anytime you want one just take it out of the freezer (it won't stick because of the wax paper) and microwave it for 10-20 seconds. It should be soft and flexible! Keep the wax paper in the Ziplock because you can reuse it with a new batch of tortillas.