1, people live in the real world, you have to face it, no matter success or setbacks, your friend can objectively face the real world life, he knows exactly what the real world is like, and it may be different from what he imagined.
2. The world people live in is a real world. There are flowers and applause, but at the same time there are blows or many disappointments, so it can be seen that your friend is sometimes helpless in the face of such a world, and the pressure from all sides may make him breathless, so he chose to leave. In fact, this is an escape. He thought he left this one sadly, but in fact he jumped into another one sadly, perhaps like a moth to a fire.
You care about your friends very much. You can see the problem from his qq signature, which also shows that you are a sensitive person. You are feeling the world with your heart. Your friend is glad to have a friend like you.