What is cheating to you ?

We had an debated about what is cheating to you and alot of people said emtional exchange with another person. I feel very strong about this. I also felt the same way. I think that any emotional exchange with somone other than your SO is cheating. Once you develope that emotional connection there is no turning back. You can keep saying that you're just friends....but deep down you're really wanting something more / most of the time if an opportunity presents itself ...those people who develope emotional feeling with someone else eventually leads to taking it all the way.