You will probably never accomplish your goals in life.
At one point or another, you will realize that most of your dreams will not come true.
Even if your dreams come true, you will find out that they do not match what you thought they would be when you got there.
Most of the friends you made during your life will not be there for you during your darkest hour. When you die, very few people will be standing around you if any.
You will spend most of your life either working or sleeping.
One day you will get cancer or have a heart attack. If you are lucky, you will die instantly. But most of you will not be lucky. You will die slowly.
All marriages end in divorce or death. So even if you marry your "soulmate," he/she will potentially divorce you down the line. If you stay married, one day you will wake up to a dead body laying next to you. He or she will have left you alone.
If you are a mother and you are raising your children, they will leave you. They will have a family of their own.
You are unlikely to become rich. But if you happen to become rich, you are still going to end up in a nursing home with someone else having to wipe your butt for you. There will become a point when you can barely walk and you will not be able to avoid wearing an adult diaper.
In the nursing home, your kids will probably visit you once or twice a week. So a complete stranger will be the person spending time with you.