Anxiety caused by relationship stress is the greatest precursor to Erectile Dysfunction that men face. The International Journal of Impotence Research (2003) reports that "anxiety plays a major role in the development of problems associated with Erectile Dysfunction." Anxiety is an experience of anticipating a future threat or danger. The sympathetic nervous sytem gets ready to meet that danger by providing blood flow to your limbs so you can fight off an enemy or run for safety. Either way you need energy. But when you have no real enemy or threat, all that energy is floating around in the form of adrenalin, making you antsy, edgy and unable to relax. When you are in that state you are not up for being aroused sexually, because that would mean talking your eye of the potential threat.