I don't think that it's possible to convince most people to be more rational. It usually causes more problems than it's worth. And as a result, I often have to make white lies or pretend to believe in things I don't believe in, even though those things kill me inside. 

And the truth is, that the most rational decisions you can make for yourself are decisions that take the irrational feelings of others in account (and the immalleability of them). It's hard to empathize with the irrational feelings of others. But there may be creative ways to trick myself into accepting them.

For example, I think that "overmoralization" is one of the major sources of social irrationality. For example, people are willing to take drastic actions (to irrational extents) to punish victimless crimes like marijuana smoking. The "make-work" bias documented in Bryan Caplan's "The Myth of the Rational Voter" is another irrational bias that comes from "overmoralization" (certainly there are good reasons to stigmatize unemployment on a societal level, but the level that it takes is often irrational). And as someone with both Asperger's and Attention Deficit Disorder (both cases far more severe than the cases of anyone else I know), I've often had to take extremely untraditional approaches in order to learn as well as I can (or in other words, there are certain rules and norms that I *will* break), even though many people find these untraditional approaches to be morally jarring (which comes from the "overmoralization" of fairness and respect for the rules). Furthermore, some people do act like altruistic punishers even when it isn't in their best interest to do so (since it can alienate them from others) - breaking a friendship because you disapprove of someone's victimless action is sort of like "altruistic punishment", although it may not be actually altruistic if the person's values against that victimless action really are so fundamental to himself/herself. 

Of course, I can hide potentially objectionable things that I do from others. And I do try to think of ways in which I could be more normal (and creative ways to reframe social norms in a system that's more acceptable than me), and I've managed to talk myself out of using Asperger's as an excuse. But hiding things makes me emotionally distant from just about everyone, and I'd like to hear suggestions on what to do, or maybe on how to accept people even when they're irrational like that. And of course, I understand that enforcing the rules (in a way that people *perceive* as consistent) is often necessary for maintaining some stable system that people are inclined to trust (even though enforcing the rules often results in substantial costs in *some* individual cases). 

EDIT: In no means do I "disbelieve" in morality. Rather, I just have a strong aversion towards the word because others have abused the word beyond recognition. I'm a near-vegan who just hates it how society uses Puritan-like moral justifications to prevent others from having the freedom to have life, liberty, and the pursuit of happiness.