And for the last 2000 years we have been told to contain those emotions and to make our decisions with our ratio (the celibate for example), which didn't always got the nicest results either.
The feeling brain is the one in the driver's seat if you ask me, while the thinking brain is next to us giving guidence. Nevertheless human beings like to follow their emotions since it's the easy thing to do. Nobody is able to alays do the right thing, because that's simply put not how our minds work. In the mid 20th-century we tried to delete the feeling brain by lobotomizing people, but they simply became ghosts. We need a balance between the two, but in the first place we need to understand that we act because of what we feel 95% of the time. Only by reflecting on it, and allowing the ratio to tell us otherwise we can fight the urge of following the easy path our feeling brain offers us. Thinking, fast and slow by Daniel Kahneman is a great book about this topic by the way.
Feelings are my reality, but I try every day to be extremely aware how tricky they tend to be. They form my ego which tells me i'm right when I have a discussion with my girlfriend, that recollects all the instances where she did me wrong so I can add some extra arguments to the discussion, it tells me that my girlfriend should be the one to come to me to make ammends because she started the fight etc. It's a slick **** sometimes. And I FEEL all thse things. That's what makes it even worse. And then I need to go back to my thinking brain and put all these feeling to a different, more honest light. That's when I can see that I'm very often in the wrong and I'm being irrational. That's when I find the strenght to go to her and say i'm wrong. It's what makes me a better man. But it's damn hard.