To answer that question you would need to look at what went on before the break up and what ended the relationship.
Try and look at this logically, you and your ex would need to sit down and see if you can be friends.
A lot of emotion and blame would be around and so you need to do this very carefully but as indicated previously it would depend on what happened before the break up.
Try not to stress over this as you might make yourself sick.
A trip to the local gym, to get rid of some of the pent up emotions and also doing some very high intense exercises, let's face it you might even lose weight.
Talk to your closest friends about the possible break up because a problem shared is a problem halved.
I believe time out is a good thing till you sort out what is happening, be around people who can also give you positive energy because what has happened is definitely negative energy.
If you are able to do this then you are strengthening yourself and also putting your emotions in a good place which means you can handle whatever comes along.
Work can always be a good distraction as well, you really just need something to take your mind off the possible break up.
Having things put into perspective is also a way of handling things, you might find after you have discussed things further with your girlfriend or boyfriend that you don't want to break up because it has become too hard.