Happiness comes from inside, though it feels to come from outside (things).
Yes, events of the world do influence us. We feel so because we think we’re bodies, but when it becomes clear that we’re souls, and not just bodies, we just don’t care and continue to be happy.
We’re concerned about events since we’re unsure of the current situation; whether it will remain so or not. But when we know of soul that nothing can at all destroy us or even disturb, then events in the world become irrelevant.
To add, true everlasting happiness comes only from God, and God has told that he dwells in hearts of all living organisms. So, happiness comes from inside.