Because they want to. Because your roads diverge. Because you have nothing more to give to each other.
It seems so simple. And at the same time, it's so hard to grasp. It always seems as if you can make things right. Rewind the events, like a film. Cut it out. Cross it out. Rewind. Replace the frame.
But no. You can't. Some things can't be fixed.
You can't keep someone around by force. You can't bring out feelings in another person that aren't there. You can't make anyone love you.
It happens that yesterday you were talking normally, sharing your worries, spending time together, you couldn't get enough of each other. And today you suddenly find yourself looking for a replacement.  One day, all the loose ends are cut off in an instant. Just like that. And there are times when the cooling off is gradual. You don't get kicked out the door right away. They just push you away. Postpone meetings, quickly winding up conversations or communicate in such a style that you yourself are in a hurry to disconnect. And if you begin to analyze, do not even understand - well, how so? Why? Why? It was cool. We were close. We were on the same wave.
We were... weren't we?
What was it for? The answer is obvious. There's no mystery. There is no special magic. No need to go through all his phrases, to remember every conversation down to the last detail, to scroll in memory of every meeting.
Why do people leave? Because they want to. Because they can. Because they don't care. Because they don't see the point in continuing to communicate. They don't see the benefit. The high they don't feel. Because they don't want anything more from you. Because they don't want to give you anything either. Because the relationship is over.
There is no point in analyzing it. There's no point in running after the person. To impose, to demand an explanation. Whoever left is gone for good.
Learn to let go. The harder you hold on to someone, the more likely you are to lose them. And you'll lose yourself along the way.
That's the worst part. To completely dissolve into another person. To voluntarily lose your own identity.
It has nothing to do with friendship. Or love.
It's a disease.