The Economist weighs in on trends in English marriage and divorce, pointing out that divorce rates have been declining recently. Based on their graphic, I would say, "slightly declining or treading water." Although marriage rates have declined, then, their point is that maybe the unions that are formed are actually stronger on average due to a selection effect.
Fair enough. And I think it might be true that never getting married rather than getting married and then divorced could be less painful and therefore preferable. But I'm not sure that's really clear.