I absolutely agree with the sentiments but -- and it is a big but -- it's like we have to go out of our way to avoid stereotypes and placing a woman as someone's whatever.
I'm a woman: I'm my mother's daughter, my brothers' sister, my husband's wife, my childrens' mother. There is no problem with me being any of these things in fiction, or in anything else. In fact, not to be these things makes a farce of characterisation.
Where, perhaps, I have more of a problem is how often men aren't presented in the same way: A mother's son. Too often, our male protagonists are off battling the powers of evil (or whatever, the coffee machine...) without reference to who is important to them, who has shaped them, who matters to them. I think this is especially true of sci fi, but that's my current obsession, the lack of strong relationship in some of the genre. Instead, it's about the mission, the plot and not the stakes for the person.
Eg (and I'm just going to take the three most recent genre books I have read, without selection or agenda and look at the protagonists):
Logen Ninefingers in the Blade Itself -- his family are referenced, but are dead. They have no interaction with him. He mentions no wife (that I recall). Glotka - we know a little more about this, but there is no real exploration of the fall out from his past on his family. Jezal has a relationship with a woman who is introduced first and foremost as someone else's sister (although to be fair, she's a pretty good secondary character and far from one dimensional).
The Shining Girls -- Kirby is shown with her family relationships, we see her with her mother, hear her mother's response to her trauma, see the interplay. Dan, we hear of his ex-wife, but we don't know him outside of his interactions with Kirby/work.
The Dome (which I reread last week) -- Barbie the loner, with no one to define him. No mother mentioned, no father, no children. Just his past work and the friends around him.
Now, maybe I'm unlucky and just have picked a rubbish selection, but this to me is unreal -- that a man should not be defined by who he is touched by, who he belongs to. It makes them less than real, three dimensional characters. So, whilst I absolutely agree a woman should not be in something as X's girlfriend if she has a role of her own to play and is central, I think we shouldn't be afraid of making her someone's mum, wife or daughter, especially if this is some of what drives her actions. And, I think, we need to see this more in male protagonists, and that half the problem lies in how they're presented. ?
