As a group, we can only judge specific contexts and specific examples we're given. Generally speaking, your way of thinking is not always right and not his either. Some things are better well defined, some are better with emotions, and some are not necessarily better with one or another. It really depends on each individual matter and if both parties are being reasonably considered per issue.
So tell me an example of a situation where a relationship issue is better handled approaching it objectively? The evidence based models of couples therapy would not agree with that. That tends to lead one person to think their version of the facts is correct while the other has the facts wrong and that framing doesn't generally resolve arguments like this.
It's not about whether something is well defined or fact vs emotion but rather is the truth being recognized by all parties as each person's subjective interpretation of the events at hand, or is someone assuming their way of viewing the situation is objective?
If you are unaware of your own biases and unaware of the difference between what a camera would record vs what you are saying happened and the language gaps between them (e.g. "she turned and left the room" vs "she stomped away" or "he didn't respond back" vs "he ignored her" or "she began speaking more quickly and animated" vs "she threw a fit") then you are not able to reliably report whether you are viewing a situation objectively.
Most of us are not as objective as we think we are, even if we have gathered a lot of data - especially if the topic is stirring any emotions/confusion etc.
Someone thinking they are being objective when they aren't can even be somewhat dangerous.
I don't believe that facts should never matter or that there should always be space for shades of gray but I do believe that it is rare to actually be objective about a relationship issue if someone is fully emotionally invested in that relationship. It is not common to step outside yourself and see just what a camera sees when it comes to interpersonal dynamics that cause conflicts with other people.
This happened then this happened is just facts and potentially objective depending how things are worded. But a relationship conflict isn't about facts. It's about interpretation, meaning, etc. usually.
There's a reason couples therapists encourage people to stop rehashing and stop focusing on facts and deal with what's happening underneath the argument over who remembers the minutia more accurately. You don't resolve the conflict by trying to prove your objective correctness.