“Nostalgia isn’t the truth; it’s just something you want to be the truth today.”
Alex is only 19 years old. He is 6ft 1; he has dirty blonde hair; he has green eyes. He has never experienced nostalgia. In fact, he is entirely against the concept of it. Nostalgia is a lie your brain tells you. In reality, you just want an escape from your current moment. Then in two years time, you will yearn for that moment.  Alex is aware of this.
Alex merely rolls his eyes when his friends talk about their nostalgia for their childhood. He knows really they are just scared of growing up. To cover up their fear, they talk of nostalgia. He does not feel nostalgia. It is a lie. He tells them this often. They no longer tell him of the fuzzy feeling.
When Alex thinks of his childhood, he has no feeling. He thinks he had a nice childhood. He was happy. He is also content now. He does not feel nostalgia. He does not wish to return to the past. Nor does his critically look at his past. He does not think of the past often. He focuses on his studies.
Alex’s friend Jack calls Alex unhinged. Everyone feels nostalgic sometime, weren’t you happy in the past? Alex does not understand how this would reflect his mental state. He has no fondness for any period of his life. He will grow old. He will participate in many events. He will enjoy himself, and move on. He does not hold on to something that can never be relived. It takes up too much time. It is pointless. Nostalgia is a lie.
Alex has only been in two relationships. One when he was 10. It lasted a week, and ended over Alex’s lack of commitment. Susan told her friend that she still thought of Alex a month later, she missed the times they spent together. Alex said this was silly. What is the point in living in the past? He would much rather focus on the now. Susan called him a stupid boy. She now lives with her on-off boyfriend of two years.
Alex’s second relationship was more significant. It lasted 7 months when he was 17. He had become quite accustomed to this person, they did not believe in living in the past. They thought the concept of complex emotion devoted to the past was a strange thing. They were quite happy together. However, Holly’s family moved across the country. They both accepted that long distance was of no use when neither could drive nor afford transport. That was the end of that. That was the first time Alex felt sorrow of his past, wishing he could go back. He despised it, and buried it deep. He refused to believe it was real and chalked it up to bad meat he must have eaten.
Alex now rejects any potential relationship. He does not like feeling vulnerable. Nostalgia leads to vulnerability. Instead he focuses on his studies. He likes learning of war. He reads books. He sees his friends. He drinks. He is happy. He is sad. But he does not pine for the past. He revels in his current emotion, whether it be positive or negative. That makes him normal.  He knows the earth moves on, whether he is nostalgic or not. He knows they will travel around the sun, again and again. Whether that is captivated as years, months, days; it can never be re-versed.
So Alex will carry on living. He will grow old. He will admire the world a day at a time, learn from his mistakes, but not dwell on them. He will carry on, he will grow old, he will die.

That is just how the world works.