its impossible to date your colleague without affecting your professional relationaship!!even u repeat it innumerable number of times, the truth would not change that u tend to expect more and give less which becomes even more apparent when u r dating someone at the ver place u work!! apart from this, there will alawys b a tendency to keep a check on the other one(again distracting you from ur work) and also, to get bored of spending so much time with each other!!