It's really hard to be an author when people know you're an author. If you're really going to write that book, you're going to have to face some uncomfortable moments. Here's the piece of advice you really need if you're really going to do this: don't hold back. In other words, when you're writing you have to stop worrying about what your mother might think.
Well, I Can't Write That...
I've been pretty forthcoming about my rampant inability to write sex scenes. It's a problem I've always had with my writing, because the inevitable thought always creeps in: one of my parents might read this. This thought is so daunting, so overwhelming, so completely terrifying that I always end up wimping out. Euphemisms are where I live. But this is a horrible flaw...and I implore you not to repeat it with your own writing.
Because if you're going to create really good writing, you can't hold back. You can't be daunted by the thought that your mom might blush at that sex scene, or your ex might somehow read your book and recognize himself in your main villain. You can't worry that your third-grade teacher will pick up on that grammatical error you keep making, or be afraid to drop the f-bomb because you think your pious brother-in-law won't be able to take it.
You can be as careful as you like, and you're still going to end up writing something that causes someone to blink twice. So stop thinking about what any of your potential critics might say, and write what you need to write to tell the story that you need to tell.
If you write something that offends a family member, you might have to smooth over some ruffled feathers. But the alternative is that you end up writing something that isn't really true to who you are, because you held back. Which reality would you rather face?