Both heartbreak and work are among the more universal phenomena in the world, but they're also not exactly the most compatible. Like any other emotionally intense event, going through a breakup can make it difficult to concentrate on work, but if you're like most employed people, that work still needs to get done. An article in Lifehacker offers some tips and tricks for how to stay focused when all you want to do is eat ice cream and listen to sad music. The piece goes into each item in much more detail, but in short they are: 

1) Focus on smaller tasks; 
2) rather than try to suppress your feelings entirely, schedule some brooding time; 
3) but not too much: try not to dwell on it; 
4) stay far away from your phone; and 
5) build a new routine.