There was once a short-tempered hosteller named Kartikey. He was a very confident and friendly kid. On a Friday evening, he went out with his friends to party at a club. He does neither drink nor smoke. He believes that he is not supposed to do any of the things that will let his parents down. He was not able to talk to his parents on that Friday due to the party scenes. The next day, he slept off in the morning, and it was already evening when he woke. He called his mom after dinner, but his mom didn't pick up the call. Acting childishly, John became irritated by the fact that he hadn't spoken to his mother in two days, and she still hadn't picked up the phone. His mom rang him several times, sent messages on Whatsapp saying that she was struck in the traffic while returning from the vegetable market. He ignored those messages and dozed off again early on that Saturday night.
It is often said that you take the ones you love for granted. He got a call from his father late in the night, around 1 AM, saying that his mom was no more. She met with an accident while coming back from the market. John was shattered. He hoped to rewind the time and wanted to talk with his mom one last time. Ask her to be safe in the traffic. Say sorry to her for not being a good son. Say "I love you" for one last time. Was I a good son? What if I had not been a prick and picked up her call? She would have been alive in that case. Was she in a hurry because I was not picking up her call? John was devastated. The night was dark for others but darker for him.
Life is what you have today. Do not repent of the past or waste it thinking about the future.