A recent study showed that grumpy people and those under stress do not have shorter lifespans than happy people. The norm was that unhappy people have more stress in their lives which equates to higher blood pressure and other ailments. But in a large sample study, that could not be proven.
Another study concluded that lonely people had shorter lifespans. How to quantify the amount of loneliness to shaving years off one's life is unknown. But it would seem that depressed people would be more sad and despondent which could led to chemical imbalances in their system.
So it is possible that grumpy, stressed people who have friends can have a normal lifespan.
The reason is simple: people with friends can unload their inner burdens on someone. Keeping troubles bottled up inside you may be the root cause of ailments, mental or physical. By having a supportive release makes sense since navigating personal decisions in life can be hard and daunting at times.
The more powerful, negative emotions may cause the most lingering problems. Anger, spite, frustration that wrap around someone being mad at someone else or something in their lives can be like constant large waves crashing on your psyche to erode away your thoughts and dreams.
In human relations, the most powerful tool a person has to neutralize the negative emotions is forgiveness.
To forgive means to stop feeling angry or resentful toward (someone) for an offense, flaw, or mistake; or used in polite expressions as a request to excuse or regard indulgently one's foibles, ignorance, or impoliteness.
To ask for forgiveness is hard because it means you must accept and speak out that you made a mistake. On the other hand, those who feel they have been wronged or hurt by another person who is asking for forgiveness may question the sincerity of the act of forgiveness.
Friendships are like a roller coaster; there will be ups and downs. It is the overall ride that matters. If one cannot forgive a friend for a mistake, then that person truly is not a real friend.