Damn, just wanted to play the game my way, but I guess it's your way or the highway and I'm the stupid one for trying to play it however I like.
Let's be real:
1- The game allows you to choose what paths YOU the player opens.
2- The story is composed around a family, that love each other, and are close to each other, depending on YOUR choices, that closeness includes Sex
3- Refusing or simply ignoring their attempts at deeper closeness, is YOUR choice as a player, the characters know nothing about it. They will react to your behavior.
4- You are applying your expectations of behavior to the game, we are all sorry that you had to grow in such an emotional desert, but many of us had the marvelous childhood and Young Adult experience of being close to our Mothers, Sisters, Cousins, Aunts... With many Movie Nights, Beach and Pool play, Camping and more, so much more.
5- Except for the sex part, most of the interactions that are depicted in the game, are common. Really common. Families do touch each other, hugs are frequent, love languages include kissing, tenderness, touch, cooking, playing. And to be frank, in some cases, it even includes sex.

I know, it's shocking... but, incest isn't a problem in many places around the world, in some cases it is permitted, in others it is simply absent from the legislation (except as an aggravating for rape). In others it has conditions, like no minors involved...
6- Your narrow views of family interactions are YOUR problem to solve or ignore, not the Dev, not the game and most certainly NOT us.
Identify, Adapt & Overcome. This is what you must do to your world views.
Peace
