I will not attack your doctrines nor your creeds if they accord liberty to me. If they hold thought to be dangerous - if they aver that doubt is a crime, then I attack them one and all, because they enslave the minds of men.
Inevitably I draw on my own relationships when I write, so if I'm writing about a fight between a husband and his wife, of course I'm going to think about a recent fight with my husband. Or if I'm writing about sisters, of course I'm going to think about my sister.