[Lecture mode]
Many traditions are of a more recent data than we care to admit, for example the traditional Scottish Clan Tartans which were more or less invented by an enterprising textile industry in the 19th century (this and many more interesting examples of modern invented traditions can be found in Eric J Hobsbawms book "The Invention of Traditions".)
Interestingly enough same can be said about prevailing moral guidelines for family formation etc. At least in Europe (including the UK) from the 17th century onwards family formations other than the nuclear family have been much more frequent than conservative actors like the church want to admit (i.e. single parents, cohabiting couples or common-law marriages). So what exactly is a tradition or a traditional way of life? More often than not it's an idealized picture of the past arranged to suit contemporary social and political needs.
[/Lecture Mode]
Sorry, couldn't resist the temptation
As you maybe can guess I belong to the progressive camp, but am not without semi-traditional traits. Though not married, which is quite common in Sweden, I have three kids with the women who has been my partner for more than 25 years. I buy flashlights (read: lots of flashlights) and she is more inte shoes (read: lots of shoes), come on, could we be more traditional in our gendered preferences? But, and I think that's important, I do not think that my choices and way of live are better or superior than any others (for example married couples, gay couples or single parents). Most traditional or conservative people I know are not that liberal, they start moralizing about others very easily.