I had the same thing happen - had it bad then it went away for a few years and then came back hard. It's been up and down since then. My theory is that it goes with my life circumstances. The happier and more confident I am the less I stutter. With me it has a lot to do with anxiety and amount of sleep I get. I can recognize that when my voice is deep it's a sign that I'm confident and I don't stutter much. If my voice is high or nasally, then I'm more likely to stutter. I hope that shines a little light on your situation.