Gaaah. Wrote a long and thoughtful response to this which promptly disappeared into the ether...
To sum up, I think both World Wars have profoundly affected our understanding of family relationships, and in turn psychology and psychotherapy have been shaped by a perception of normality which is actually anything but.
For instance, it's now generally accepted that adolescence is a challenging time, a time of 'storm and stress', and that there is a generation gap, so parents cannot hope to understand their children, and vice versa. But when you look at when these theories were formulated, you realise that parents who grew up in the 1940s went through all sorts from rationing to extermination camps, and were either hardened or traumatised. This was not a great foundation for a happy family life. Meanwhile their 1960s kids enjoyed life, developed ambitions and ideas of their own, questioned their upbringing. They could not hope to grasp what their parents went through, and their parents expected their gratitude to heal the emotional war wounds.
I think we're still living through the consequences of this generational split, trying to feel our way into talking to our kids again. But the so called professionals keep telling us that teenage distress is normal and expected and that it's not a problem for the generations to isolate themselves. (Unless you've done something wrong, of course, like allowing them to watch Teletubbies when they were three, or talking to them in the wrong pitch.) I think we're still working through the fallout of war in our families.