After both have given all they have, what we gain is love. As long as we have love, we are happy, no matter how much we have invested. Since this is the love principle, God started the creation based on love.

God would not invest in anything that would not produce a benefit. Giving all one has creates a minus, so why do you think He did it? Because love has the power to more than fill up any void, after expending and investing Himself, God gained love in return. True love does not become smaller as it is invested, but grows bigger and bigger the more it moves. Conversely, if the principle were that true love would grow smaller, God would be depleted through His investment. But the opposite is the case. True love grows bigger and bigger the more it is invested.