Hire a rental car, buy a shovel, a jerry can with petrol, a lighter, make a balaclava, buy some rope and some milk n cookies.
Drive to her house, drink the milk n eat the cookies, wait for her to leave/walk to house and hit her with the shovel, tie her up with the rope (double knot to be sure), stick her in the boot/trunk n drive to a nearby quarry or bog/swamp, and bury her/dump her there. And burn the car.
Or just look into the reason why u broke up. If it can be fixed or solved then fix it first then prove you can make it work otherwise just move on. Shit happens .. Life's a bitch then u die etc etc. just sit it out for a week or two then go out to a bar or suttin, meet someone else n move on with life.
If u break up with someone and your life doesn't crash n crumble to a point where u become a nervous wreck then u didnt love her as much as u thought u did.
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Also: did u atleast have break up sex!? If not ring that bitch now and demand it!