I'm an only child, so the sibling aspect isn't something to which I can relate. But I can relate with feeling like you don't fit in with your family, and that your parent(s) are stifling your personality. My political/social views are the exact opposite of those of one of my parents. It feels as though, on the rare occasions when we do speak, it's only because we're related and we have a sense of familial obligation. In choosing friends, I tend not to associate with people whose beliefs are so radically different from mine, as there's little we have in common. The same is true for my parent. When the crux of your fundamental beliefs are the opposite of someone else's, it's difficult to have even a lighthearted conversation about a movie or a TV show without offending that person.