I was pretty happy before LW, until I learnt about utility maximization. It tells me that I ought to do what I don't want to do on any other than some highly abstract intellectual level.

Two things seem off. The first is that expected utility maximization isn't the same thing as utilitarianism. Utility maximization can be done even if your utility function doesn't care at all about utilitarian arguments, or is unimpressed by arguments in favor of scope sensitivity. But even after making that substitution, why do you think Less Wrong advocates utilitarianism? Many prominent posters have spoken out against it both for technical reasons and ethical ones. And arguments for EU maximization, no matter how convincing they are, aren't at all related to arguments for utilitarianism. I understand what you're getting at---Less Wrong as a whole seems to think there might be vitally important things going on in the background and you'd be silly to not think about them---but no one here is going to nod their head disapprovingly or shove math in your face if you say "I'm not comfortable acting from a state of such uncertainty".

And I link to this article again and again these days, but it's really worth reading: http://lesswrong.com/lw/uv/ends_dont_justify_means_among_humans/ . This doesn't apply so much to epistemic arguments about whether risks are high or low, but it applies oh-so-much to courses of action that stem from those epistemic arguments.