I heart you Sunni but you don't know that to be a fact.. Libertarians err on the side of freedom, liberty. Take same sex marriage, the Libertarian Platform actually supports it- not because it condones it but because libertarians want government out of the business in legislating morality. While my belief is that homosexuality and abortion are wrong, I don't want the government forcing that morality on anyone.. Just as the government has no business in legalizing it either. You either support liberty or you support fascism.
Libertarians do not support gay marriage. They support the government being out of marriage entirely. That means they would take away your married tax return, your Social Security survivor benefits, and the thousand other cash and prizes government gives to you for being married.
They would also take away your mortgage interest deduction, your child tax credit, and every other tax deduction, credit, loophole, and boondoggle of which you currently take advantage.