Whatever happened to the idea of getting married?

Since when is it exciting news when Jessica Alba, Halley Berry, Nicole Richie, Tom Brady and other celebs think getting pregnant (=or in Tom's case, impregnating someone) without getting married is a good thing? Since when has the institution of marriage been replaced by openly sleeping around, shacking up and bearing illegitimate children? It's shameful and unGodly, and anyone who's doing it and saying they believe in God and follow His guidelines is lying.