Heartache is a sickness, manifesting itself not only emotionally, but quite physically as well. Symptoms include, but are not limited to, loss of sleep, nausea, painful tightening of the chest, inability to self-regulate body temperature, and uncontrollable shaking. Depending on how you handle the situation emotionally, you may also experience chronic dry eyes and/or a sore throat.
In the absence of love, however, it is often better to feel horrid than to feel nothing at all. Through heartache, at least we are still aware that we are alive.