Yes - but that's what I'm saying - only one of the many people I know that have been divorced at some point in their lives (some are now very happily married) left their marriage for a reason other than emotional, physical or verbal abuse, or because their "D"H had run off with someone else (actually one of them ran off and left her DH but).
And unless you're actually there in their life you don't actually know what the problems are, or how deep they run, how long they've been going for etc. My parents to this day don't actually know what caused me to finally leave my marriage (we'd got back together for a while but then I finished it - with good reason)
I was also "woosy" child that didn't know how to stand up for myself, I was bullied, my parents were of the ilk that I had to learn to stand up for myself, so although I told them some of what was happening at school I didn't tell all of it - as I knew they thought I should be standing up for myself. I ouldn't stop the bullies, the teachers didn't stop the bullies, my parents didn't stop the bullies.
The result??? Most of my adult life so far suffering from low self esteem, recurring bouts of depression a wasted decade of my life (apart from my lovely DS's) . (thankfully in the last year or so I have managed to shake most of the issues off and start living)
My brother suffered the same fate as me at school- except it's affected him even more and in his mid 30's still hasn't overcome many of the issues, still lives alone with few friends.
Some children - are naturally strong willed and confident and can easily "fight" (not in the physical sense I hope 
) against stuff that happens to them. Otherise are naturally more shy, and reserved, and yes - you can encourage then, and try and teach them how to stand up for themselves, but you can't force the issue. And until the day comes when they have found the confidence to speak out for themselves someone has to do it for them.
Having said that I do know that some parents are helicopter/cotton wool parents. But I don't believe we're breeding a nation of "woosy" children/ There have always been parents like that, there always will be.
Tbh - I'd rather have a nation of "woosy" children who head into adult life (while perhaps a little naive and needing to quickly learn some "Real life" skills) feeling that someone was looking out for them when they were children, and with good self esteem and no "issues" already there to deal with before they even hit the adult issues in life. Than a nation of people who had to go through what I, and many others, did.