The thing you used to do, which was lacking in some way.
I used to be a loyal follower of Traditional Rationality. Emotions were the enemy, frigid logic and reason were my allies. Combined with a burning desire to win at all costs, it sort of worked. Since I wasn't learning from a specific person, I even managed to reinvent a lot of stuff from true rationality (in a hazy, unspecific sort of way). But the emotion thing... I was miserable, and my response to that was to bury those feelings instead of carrying out the introspection necessary to figure out why I felt so bad all the time.
The rationalist concept that challenged your habit.
Yudkowsky's vision of a unified rationality+emotions, and Kahneman's S1/S2 model of cognition, particularly the idea that S1 had something valuable to contribute.
I had heard all the standard "don't bottle up your emotions" advice before, but none of it addressed the fundamental problem that I wanted to win -- and as far as I could tell, emotions were nothing but dead weight. People who were emotional lost. They got angry. They cheated on their relationships. They flitted around life, tugged on a leash by their feelings. There was no focus, no coherence, no master plan behind it all. Just chaos. It seemed to me that the choice was to either be strong and cold, or weak and warm.
Reading about an alternative to what I was doing that didn't have massive immediately obvious flaws... that was enough to convince me to start the introspection process instead of ignoring how I felt.
What you do now.
I don't feel like crap all the time. Turns out there was quite the surprise waiting for me at the end of the rabbit hole (I'm trans), and now that I'm addressing the root problem, all the negative side effects are disappearing. I don't believe in a rationality vs emotion dichotomy anymore. I'd like to say that this has spread into my general behavior, but unfortunately it's only been a few months since my crisis of faith, and it takes longer than that. But when I catch myself trying to quash a feeling, or disregarding an intuition, I stop and ask myself whether this is the sort of situation where intuition would reasonably be expected to work well (frequent, rapid feedback, etc).