Hey man, don't give up. I have a closet full of broken bows as I was learning to make them. Lots of them weren't even broken during tillering, but rather during a phase when I had no idea how to work with my tools. Others broke after several hundred shots. For various reasons, I gave up at that point. Now I'm back into it. Broke one bow just as I was bracing it for full draw (I'm slightly suspicious that I need a bow stringer...), and just finished one last night, though it's out of tiller and took massive set (mostly from being strung, picked up an inch and a half or so each time the brace height was increased), so I'm gonna pike the weaker limb and recurve the whole thing when I get the chance. Then I'm gonna run out to the hardware store (lowes. I find the home centers are easier to find good wood at. The hardwood store by my house has so much wood in it that getting a look at every piece is damn near impossible, and very few pieces have decent grain, whereas at lowes and home depot, it seems that one in ten pieces is usable, and 1 in 4 with a backing.) and buy a nice maple board and get cracking again. And then I'll do it again! Its a matter of practice.
Try and analyze why and how each bow broke. Did you ignore/miss a hinge? Did the wood get too dry? Was it a bad piece of wood? Knowing exactly why and how each one broke will teach you more than anything else.
