how do we know what to offer up vs what to address?

If it's just about your personal preference. Then 

If it's a threat to your physical,  emotional , spiritual and relational well being, then you should speak up and address. Anything that  undermine your dignity as a son of God, or demeans your dignity as a person. If that person refuses to meet those needs, then speak up.

But if an offense is a threat to your preference, like I prefer it this way than that way, like I prefer the toilet seat up rather than down, these are minor irritations and u can offer it up as a small mortification. Or things that are out of ur comfort zone, you can be generous to offer them up, and even grow as a person to experience these things. 

But if the offense against my preference is persistent or pervasive, then speak up. Like if it always happens despite you gently raising it up, we should be in a relationship that has mutual self-donationship. For a healthy and thriving rs, it need to be mutually self-donative, and not one sided.

Use SOLUTION FOCUSED language rather than EMOTIONALLY FOCUSED language to address problem.

- criticism is emotionally charged, eg. Calling names   vs a complaint which is solution focused eg. You didn't top up toilet paper so can I put a basket of toilet papers here to make it easier, what you think of it?