My biggest insecurity? That readers will think my writing (and my ideas) are weird and un-relatable.
Another big one? My main characters tend to be passive, introverted types (like me, huh, imagine that!) Everyone wants STRONG main characters. Pro-active main characters. People who make daring and risky choices and speak up boldly!
In my first novel, my character never made any choices or did much of anything active except follow others. Things kept happening to her, pulling her and pushing her this way and that. My wonderful fellow writer/critiquer, code name Lorvallis Scholar, pointed out, "your protagonists needs to protag!"
And forcing my character to make a choice early on in the story was definitely the best thing that ever happened to that story; it was a revelation.
So in the next three stories I've tackled, I've forced all my protagonists to make a tough choice early on.
But somehow after that choice they revert to their passive, introspective nature again - thinking about things but not actively pursuing things. I constantly fight this tendency. If I make them too active and loud and blustery, it feels all off to me. Even though I love active, mouthy, bold main characters in other books. I adore them!
But then again, I also love main characters like Meg in A Wrinkle in Time. Sure, she makes a choice (near the end of the book). But most of the book she's being pulled along by Mrs. Whatsit and company and by her little brother Charles Wallace. Her little brother is more active than she is!
Another favorite character is Harry Crewe in The Blue Sword. She gets kidnapped and doesn't even fight it! She's carried along by a strange magic, kelar, and doesn't make a truly active choice until near the end of the story (but wow. what a choice). And though at first I really questioned myself why I would like a girl like this, who doesn't fight her kidnapper and even falls in love with him (ewww the Stockholm syndrome!) the author does an commendable job of developing the plot so there is a very good reason why Corlath needs to kidnap her, and why she doesn't resist him until she needs to resist him.
Shadow and Bone, by Leigh Bardugo is a more recent example. Alina is as mousy and uncertain and indecisive as they come! But I love her story. She makes some bold choices but again they don't come until near the end. Hey, come to think of it, Girl of Fire and Thorn by Rae Carson is another one.
So now that I've faced my insecurity about having a passive main character, I have to face the insecurity of building a strong enough plot (like the four stellar examples above!) to make such a character believable and relatable and not just "I wish she'd grow a backbone!"
I used the image of Katniss Everdeen and Bella Swan because it's a famous contrast of a strong female character that speaks her mind, and everyone admires, versus a passive helplessly-in-love girl that lately everyone seems to despise.
Now I'm way too insecure (ha ha) to tackle the Katniss vs. Bella issue myself, but there are opposing views on what makes a strong female character out there, like this one. Stuff to think about! But really the bottom line is, everyone has different likes, different desires, different ideals of what they love in a main character. No main character is going to connect with everyone out there.
So we have to believe in what we write (after we have taken the time to be well-informed) , in what ignites our love and drives our imagination, and go for it. Insecurity, begone.