Is church unfriendly to the unmarried?

I've just read the book After the Baby Boomers, and the main take-away I got from the book is a feeling that the church isn't doing a good job ministering to young people who aren't part of "families". We put a lot of focus on Family Ministry, as being the alternative to ministering to mostly empty-nesters and the elderly. But what about all the people who don't fall into either category?

After the Baby Boomers looks at a LOT of statistics, and one that jumps out is that there is a huge gap in church attendance between people who are married and those who are unmarried. Being married makes you much more likely to attend church regularly. And yet, overall, the rate of marriage is decreasing among younger americans so that being married with children is no longer the norm but the exception for those in their twenties, and is becoming less the norm for those in their thirties.

Correlation is not the same as causation, or I could say "which comes first, the chicken or the egg?". Do people who go to church because they just have some sort of "church personality" also get married younger for the same personality reason? Does church attendance mean that you value marriage more and are there-for less likely to choose an "alternative lifestyle" (calling the norm "alternative" is silly, but in this case it's alternative to the traditional)? Or is church culture unwelcoming to singles?

Even if it's a combination of all of those reasons, the only one churches can really DO anything about is the last. How can we better welcome single young people and what ministry do they need in this stage of their lives?