HD, That just makes me sad for your older kids. They should never be put in the position of feeling that they are "less" than D3.
As far as corruption, I think that your wife is just reacting to this normal parental phase. SOMEONE, SOMEWHERE is going to corrupt her. Little girls are so perfectly innocent at that age and then they start to pick up on the ways of the world and people around them. It truly is a sad thing to witness!
I think it is fair to say that you will be setting boundaries as far as what the older ones are allowed to do around the younger ones (into which I would lump your D9) but that you love them as is and have no intention of undertaking a personality overhaul on them--imagine how devastated they would be if they suspected that their own father didn't 'like' who they were! (and btw, what dad truly likes who his kids are while they are immersed in their teenage years?) This would be the approach I suspect you would take if all of these children were yours and W's..you would set boundaries about what they were allowed to say or watch on TV or wear around her.
Along the same lines, we went to a graduation party this past weekend and my FOURTEEN year old niece was sporting around in a skimpy bikini with a tattoo on her ass and a playboy bunny reverse-tanned onto her belly. (is that what they call it when they put a sticker over a spot and then tan the crap out of the rest of their skin?) Oh and a belly button ring. I was mortified to have D4 looking at her...this girl who up until this year has been a good playmate to her. And hoping she didn't ask any questions about either the bunny or the tattoo. (I have a tattoo myself so she is probably immune to that but I want her to understand that they are for ADULTS to get, not kids who can't even freakin drive themselves to get one!) It just gave me a sick feeling in my stomach to wonder what this little girl thinks she is advertising about herself.
Anywayyyyyy, I digress.
I agree that she was probably unconsciously picking a fight with you, in order to avoid having to be affectionate to you. People are weird.