Are you using a desktop or laptop? I used to carry my laptop around with me to use whenever wherever as designed, and found myself always using it. Setting aside a dedicated desk space where I limit the use of the laptop made it much easier to just think of it as desktop and less mobile. Now, using it feels like I'm at work, and it is much easier to walk away from it.

Finding other things to do when bored instead of opening a browser is key. You're going to fill the time with something, so you have to find the something else.