I imagine you are in a romantic relationship. Over coffee, you ask yourself this: Why do I feel like I love him and hate him at the same time? Or, you've been together for several years and the romance has already gone abroad along with the sexual desire. And you ask yourself: why am I still with him? Hard to explain.
It follows that the cognitive machinery fabricates reasons. Let me tell you the tragicomedy based on an excellent social psychology textbook.* Experimental research shows that as you analyze the reasons, the attitude tends to change because (a) the conscious mind makes reasons that don't really reflect what you feel, and (b) you start to believe that this is how you feel based on the reasons (correspondence effect).
In one study, Wilson and Kraft (1993) asked college students involved in romantic relationships to write about why things are the way they are with their partners. Can you guess what happened to their relationship attitude? This made them change their attitude towards how their relationships are going. To see how! If they wrote positive reasons, they became more positive, and if they wrote negative reasons, guess what, they became more negative. That's not all, nuclear has just arrived, as written in the tabloid news. The surprise is that over time, the effects of ratio analysis wear off and the initial attitude of "difficult to explain" returns. And look how, you make trouble!
Transcendence? If a person makes a serious decision immediately after considering the reasons, such as breaking up with a lover, it can be a regrettable decision. How is that? Because when looking at reasons, people tend to focus on what is easy to put into words, while ignoring what is difficult to explain. The brain prefers to (unconsciously) replace difficult questions with simple ones. That way you can respond with minimal effort. But those hard-to-explain feelings matter in the long run. They usually come back after a while. That means fighting them again. Of course you don't want that.
It is worth remembering that it is difficult (and even impossible) to figure out exactly what we feel. Great attention also to some psychotherapists – specialists in introspection and psycho-abysmal analysis.
*Elliot Aronson, Timothy D. Wilson, Robin M. Akert, and Samuel R. Sommers. Social Psychology (Ninth Edition). Pearson, pp. 120-130.