I am beyond sick and tired of both left and right wing people using "Libertarian" to refer to lunatics from the American GOP who decided to co-op and abuse the term.

Libertarianism per se has nothing to do with capitalism per se. You can have libertarianism with or without capitalism and vice-versa, at least in principle (in practice, of course, some implementations are going to be more challenging than others to design and/or implement).