Actually marraige in the West predates Christianity by a millenium at least, and existed long before the Jews had much contact with the West. Marraige was firmly embraced in both ancient Rome and ancient Greece in pretty much the same form it is now.
It is interesting that while homosexuality was frowned upon as a vice by the Romans it was tacitly accepted as a facet of human existence. Still there is no record of homosexuals being allowed to marry one another.
There is evil in every society. The key is to continue to stand up against it.