There are some useful tips to keep wire jewelry from breaking:

1) try a stronger wire.
2) place a crimp bead at the end, before you attach the clasp. This will keep your beads in place in case of breakage.
3) consider using bead caps. They're very classy, and give your clasps something sturdy to attach to.
4) make sure the size of your wire is appropriate to your bead size. Use a thicker wire with heavier/larger beads.
5) make sure your crimps are tight. You may even want to place one in under the bead cap for extra protection.

Richard Dalson