In 99% of the cases the bow is bending into the handle area when a handle pops off. The glue is rarely the problem. Even after 1000 shots it can happen because your wood has become more flexable with use. To insure it doesn't happen make sure the handle riser is above the plane of the limbs.
If you think about it, there in very little stress on the handle of a bow. As you draw the bow the pressure is pressing the handle riser to the bow.