I find it easier to get over those I've loved by convincing myself that they're missing out on the best thing that could have ever happened to them.
"Their loss" mentality. It's a combination of that and coming to the realization that everything happens for a reason. So if we're no longer together or on talking terms, if it is meant to be, they will come back. If not, then that person just wasn't the right one for me and I move on.
Granted it takes a couple of weeks, but I find its easier to get over someone the quicker you realize that and begin to occupy your mind with other potential prospects.