Has American conservatism fallen into an unfortunate slump of Ignorance and Denialism?

I used to think Americans conservatives were reasonable and wise, but lately, the opposite seems to be true lately. I can't find too many moderate conservatives out there, all of them seem to be senile flag-waving "Christian Nation" bigots who get all their news from Fox, or radical Libertarians who advocate total disestablishment of all infrastructure so Koch Industries can buy more Lamborghinis to pollute the planet. Straw-man, I know... but the majority of conservatives I come across fit into one of those two groups, or both. My grandmother is a conservative, anti-vaccine creationist, climate-change denier, homophobe, alternative medicine promoter, and advocate of "Organic" food. Whenever I offer her evidence against her causes, she just shrugs it off and denies it because "I know I'm true". My father is a free-market guy who advocates the FairTax, a very radical idea of getting rid of all income tax in favor of a 30% sales tax... giving the rich the power to pummel the lower classes. Whenever I raise the fact that the 9/11 responders can't afford health insurance, he denies it and says "Everyone is insured in this country". Conservatives claim that Obama has ruined the country, but provide no evidence other than hypocritical, cherry-picked data and anecdotes... as well as stereotypes like "Welfare Queens" extending the wait times for healthcare. I heard one guy on Fox News claim that we're "Taxing Success"... really? These guys must be genius to find such successful justifications for their own selfishness, flaunting their wealth and establishing monopolies that influence our government. These guys would have much more money than the common man anyways... take, for instance, Eisenhower/Nixon-era tax rates. We're talking 70-90% income tax rates for the richest people in America... they still lived happily while we built vital infrastructure like Schools, Highways, and other modern-day necessities. Then Reagan came along and screwed the lower classes under the guise of the cold war and other flag-waving drivel.... unions were fired, the economy was deregulated, the rich got richer while the poor got poorer. Still, everyone thought of it as a success... today, as a result of deregulation and capitalist greed we're facing a home and banking crisis as well as a debt which could cause rapid inflation, and even stagflation in our future. Republicans just shake their head and say, "Reaganomics works, it's the regulations that screwed us". I can only pity them for their inability to face harsh truths.