How stress and conflict affect you life
Stress is a natural and necessary part of life. Our hunter-gatherer ancestors developed an automatic fight or flight response to protect them from predators and other dangers. When we perceive a threat, our bodies pump out Adrenaline and other hormones that increase blood flow, boost energy levels and make us capable of doing exceptional things in the short-term, to defend ourselves. What's important to remember is that it is intended as a SHORT-TERM response - our stress response helps us to defend ourselves quickly or to get away as fast as we can. And then it's over and we go back to normal.
Modern life has done away with those ancient kinds of threat, for the most part. You're not likely to have to face down a sabre tooth cat or an angry mammoth. You ARE likely facing one or more of the following: constant deadlines, paying bills, juggling childcare, interacting within different teams and groups at work and in the community, fear of job loss or difficult conversations about job performance or what's to be done about an ill or dying relative, a cheating partner, along with the impact of COVID - possible job loss, loneliness/isolation, risk of being infected and falling ill, or passing on the virus, worry about a loved one who is already ill from it, and much more.
What comes with modern life is the cumulative negative health effect of stress that is experienced over an extended period of time. The longer chronic stress lasts the worse it gets for both mind and body. Unresolved disagreements and conflict add to your stress load in addition to affecting your relationships with the people in your life, on several levels - the first is the level at which the original conflict occurred; the second is the people who comprise your social circle and support system.
Your unresolved feelings about the conflict or disagreement have a subtle influence in your general state of mind and social behaviour could include feeling fatigued, not being able to concentrate, loss of sleep, or being irrationally irritable, with unexpected outbursts of anger in situations that wouldn't normally warrant it. It can lead to depression. Apparently sudden emotional stresses, especially anger, on top of an already stress-laden body, can trigger a heart attack.