Yes, feather the fade out onto the limb, about 2" past the flares. It will flex a little bit out near the fadeout, but less as it gets nearer the flares, then probably not at all in the narrowed portion(arrow pass) since it will be thick at that point. The fadeout is what slows and then stops the bending.
One way to keep such a glue joint from seperating is to create perfect mating surfaces, then roughen them (I use a toothing plane blade), then use a glue with gap filling properties... I use Smooth On. I NEVER have handles 'pop off'... and sometimes I really push it too... like on short bows with short dips and short flares... so as to maximize working limb area.
It also helps to stretch things out... making the fades long and low... and 'flow' nicely into the handle... no abrupt changes... sometimes it'll be hard to tell where one 'part' stops and another starts.