Some people, such ass my self, prefer not to share their women so I was wondering if sharing is optional? If so I'd gladly play this game.

yes. When the choice comes, you can choose between sharing and not sharing. Some content will not be accessible.(for both choices)

There's actually very little sharing content, like where you step back and let them go at it. it's mostly just threesomes, but if you don't like it you can just choose not to engage with it. It generally doesn't chase you around or anything and you can always say no. 

Most of the tips here are pretty solid, but there's one crucial detail the guide mentions - when Ken asks to take pics with Anna at your place, DO NOT forget to hit him with the 'Let's hang out sometime' option. Yeah, I know the game prompts you to share at this point, but here's the pro tip: on your second visit to Ken's pad, you can actually switch things up by choosing Samantha to alter your path. The other routes are kinda one-note without much variety, u know?