Personally, I make my own moral code as consistent as possible. What I hate the most is being branded as a hypocrite, not by others, but by myself. Before I subject myself to the judgment of others, I judge myself. I am my own police, my own judge, my own jury, and my own executioner. Who else can better bear witness to your actions other than yourself?
But even this kind of morality is hard to apply. I criticize myself rather harshly, berating myself for being inconsistent, hating hypocrisy.
For those who subscribe to religion, all they have to do to be forgiven is pray to their deity and poof! The sin goes away just like magic. Wash, rinse, and repeat. No need to be held accountable. You'll be rewarded in heaven as long as you repent, may it be on your deathbed or on the gallows.
There is always room for hypocrisy. Get yourself in a moral predicament? No worries! Just find a passage in the scripture that's contradictory to what you used to believe and stick with that. Anti-gay? The Bible has passages that can be interpreted to be against homosexuality. Pro-gay? Pick passages about indiscriminate love for all. Anti-abortion? Sanctity of life! Pro-abortion? Numbers 5:27.
For someone like me who doesn't believe in this codified hypocrisy, I seek out my own mentally codified set of rules, constantly amending any errors and inconsistencies. Any guilt I feel will be embedded deep into my mind, unwashed and unforgiven. I'm a cripple refusing to lean on the crutch of scripture.
I am incapable of fully forgiving myself. I am a flawed human being and I don't need a deity to tell me that.