I'm probably going to beat a few dead horses here, but I feel like I need to repeat an oft forgotten sentiment that I'm rather staunchly standing by.
Strong women, by the standards of what makes men strong, are not that strong.
Often, we see authors trying to remove 'weakness'. Keep her away from the kitchen. Remove any sense of shame, kindness, submissiveness, or display of excessive emotion. If she's fat, she can't dislike her body. If she's muscular, she can take on any man in battle. If she's skinny, she's faster but God forbid she's ever manipulative or seductive or uses her looks. She's never illiterate and she never uses drugs. She can drink anyone under the table but she's not an alcoholic. She doesn't have kids, but if she does, she's not a nurturer. Tough love only. She can use sex to get her way, but is never used herself. She can't have been raped or otherwise traumatized because that would make her a damaged prop, a cheap piece of plot, rather than a fully-realized character.
See where I'm going? Contradictions abound as the list goes, somehow making a 'strong' woman into no woman who can ever relate to her. In trying to steer clear of the Stepford wife, we're left with another Barbie, more plastic than G.I. Joe. We're suddenly making the broken women who build their own lives up again, not giving the supposedly submissive-seeming character the room to reveal that she has the agency to wear a mask to build up her empire. The 'weak' woman is dismissed as flat before her layers are shown. She is no longer allowed to be mysterious because her perceived weakness will be consigned to satisfying the male gaze, to being nothing more than a punching bag, to not having her own mind or dreams.
Time and again, you see the nervous writer asking how to write a woman and you get the floods of defensive women looking to cut them down as sexist or misogynistic or shallow if the woman isn't some ideal that removes an feminine trait they consider weak. And I didn't gender the writer because, yes, they will even presume to infantilize a woman who isn't sure how to write female's of a certain level of socialized femininity. Maybe she was raised around men and just has no idea how women socialize or never uses make-up but her character does. The problem with their advice is that their increasing departure from socialized femininity begins to villainize any women who personify that role, as if to invalidate them as real women.
The trend is even to protect trans-women, gay women, women of color. Anything but the feminine aspect. In fact, the idea that we can't even define the feminine or masculine aspects because they might cause offense are what really end up causing the confusion. So instead, anyone who finds comfort in gendered roles becomes part of the problem and....
Ugggghhhh, no more. Really.
People will continue battling this out, but as a writer, at some point I learned to just write. To look for the logic in a character's build and see if their actions, reactions and personality are plausible for themselves. To remember that I am misunderstood, that I am perceived as both weak and strong, that my stories will always display vulnerabilities and impassable walls, that those walls will crumble and when people feel safest with me, they'll sometimes hit invisible walls that confuse them as well.
If you want a strong woman, look at a characteristically weak one and ask what she might be protecting, what might be motivating her, what she is waiting for. Don't be so quick to dismiss her as weak or a victim. It's not always her failing that makes you uncomfortable but yours. Give her time to seem shallow, give her some time to be annoying and mysterious and able to change.
A strong character will not say all the right things, know all the right people, be confident in every room. They will also not be endearing in all their faults, be the pariah surrounded by peons, and suffer greatly just to prove a point. If they are any of those things, there's an organic way to get there without punching your reader in the face.
If your character is constantly signalling that they are kind but are actually stone cold assholes, then tell narration should at least be aware, making it comedic, creepy, or ironic. Otherwise, the reader just thinks you're ignorant of any device to drive the disparity.
I've said it before and I'll say it again, just be aware. At every stage of their actions, you as the writer should know what history or fears or delusion drives it. That is what keeps them from being flat. Don't try to be safe. Strive to deliver honesty at every dimension and you'll be all right. If you don't trust what you know of people, observe (but don't stalk) people who fit the bill. Don't always worry about being right. Sometimes the story is about your perspective or how others react to them in general. If you have a specific trait in mind, ask someone who has it rather than general forums that will confuse it with assumptions of their ideal.
Oh yeah, and have fun. Exercise your own strengths and enjoy the process.
