We desire to fill the need. The box represents temptation. Tempation is always packaged nice. The styrofoam peanuts represents sin. Sin is also anything less than what God has intended to fulfill your need.
Sin does, however, give a feeling of immediate satisfaction.
But just like the peanuts, sin offers nothing that you truly need. And when the unfulfilled need returns, we need more to bring us to the same point we were before. The best friend represents God. And the lasagna represents true fulfillment of your needs. The sickness later represents death, which is the only thing that sin brings.