Question: What can I do to force myself to be more rational (rather than emotional) when making decisions?
Answer: I agree with you that by default our decision making is almost solely emotional. This is not surprising since we are primary emotional, sentient creatures driven by instincts, hormonal reactions, since our basic matter is the desire to receive pleasures for ourselves.
Our own mind is secondary to our desires, emotional impressions, serving only to sort, catalog, prepare those desires, emotions.
If we want to become more rational, if we want to gain control over our instincts, rampant emotions, we need a “higher mind”, we need a unique “collective mind”.
In a special, purposefully built and conducted environment we can build such a collective mind that can neutralize our inherently self-centered, subjective, emotional tendencies. Moreover such a special network can achieve similarity of form with Nature’s integrated, altruistic network. And by the merit of this similarity we can connect to Nature’s “infinite mind database” and start downloading information, blueprints, solutions form there.
Thus the solution you seek is found in an above mentioned special environment, group.