One way to think about possible worlds is in the context of love. For
example, people often ask: would you still love me if I were poor? Would you
still love me if I had no arms? And so on and so forth. They are asking a
question about possible worlds. That possible world in which you have no
arms. Or that possible world in which you are poor. Or perhaps even that
possible world in which you are poor and have no arms.
If the answer to all these questions is "yes", then the lovers can be reassured that their love is an eternal constant between all possible universes, making them more secure in their love for each other. If the answers are "no" they can be assured that they exist in the correct iteration all the infinite possible universes, because in this one they are together.
Love aligns our place within the infinite multiverse.