OK, as everyone else has picked apart the love part...
Chastity exists as a virtue of some sects of Buddhism and several other religions, some of which predate Christianity.
Monogamy was practiced in several cultures that predate Christianity.
Romance, depending on your definition, is either a rather old concept (again predating Christianity) or a relatively new concept (appearing in the Late Middle Ages/Early Renaissance in Europe, and at other times in the last thousand years in other parts of the world).
Marrying for love (solely for love, anyway) is (depending on perspective) either as old as the idea of marriage, or a development younger than the United States. Not exclusively Christian either.
Several other religions have their own versions of matrimonial oaths, and even those without religion have oaths of their own, sometimes written by the parties involved, that they hold to. So not exclusively Christian.
Lust is not the opposite of 'true love', and one can lust after ones soulmate without suddenly losing the 'true love' quality. This is a flat out disconnect.
Lastly, as the book says God is Love and loves all of its creations, but there is no oath of matrimony between the Creator and its creations, does that mean God is Lust instead, that the Creator lusts after us? I think your 'god' may well be Slannesh.
Er... no offense, Slannesh. Smite this guy, not me.
