Before getting into how to have an intervention, let's look at why:
0) It's totally possible to be super committed and working really hard hard in your startup. It's up to you to realize that a lot of your effort likely isn't getting you a productive return. Do work in batches.
1) Your technology exists to serve you, not the other way around.
2) The world and universe will not stop functioning without you.
3) There are very few problems in life that can't wait 1-2, if not 4 hours.
4) You are not always wired in, you are always distracted. It's why you're tired, unfocused, likely unproductive.
5) Your goal is to learn to get some space so you can see the world with your eyes instead of through a screen. It makes you balanced and produce better software. Life is for living. Keyboard time is rarely living.
How:
1) Turn off everything. Go for a walk. Read a book. Notice that no one is as important as they've hallucinated.
2) Breathe. Anything you miss will be forwarded to you or on your twitter feed anyways.
3) Block everything in your hosts file and only use your smartphone to access it. Every single site that isn't productive. Hacker News should be at the top of it, including Google news or anything else that takes your time.
4) Turn off all notifications. No one is the center of the universe. My phone has no IM, VM, Email, SMS, or APP notifications turned on. I run a consulting business while I'm on call. Nothing has ever imploded. Some might be allowed to make a quiet ticking noise, or use the haptic feedback.
5) The post about meditation is really good. Learn to take many thoughts down to one, and one down to none.