Libertarians usually define liberty narrowly as "freedom from government".
Freedom does not mean the ability to do as you please, but rather the ability to not be told what not to do, or to be made to do something you do not wish to do.
A libertarian usually does not object to wage slavery, and would disagree with the concept of wage slavery entirely, on the grounds that you were not forced to work a job you dislike, since you could always choose to starve instead.

What you're looking for is one of the schools of anarchism.
Although usually painted as "anti-government, anti-society", it actually derives from being against hierarchy, and is characterized generally (there are many schools) as being opposed to involuntary power hierarchies.
Sometimes government is the best way to reduce the total amount of coercion in the system, since forcing a lot of people to pay a little can free many, many people from being forced to do stuff they loath to survive.

Libertarians aren't pro-liberty they're anti-government, and anarchists aren't pro-chaos they're anti-coercian. They're both entire political schools of thought, so I've obviously not encapsulated them entirely in two paragraphs.

Why the hell do you think that libertarians don't believe in universal healthcare?

You will know the answer if you look more specific at what exactly different people understand as "liberty"

I like the idea of universal healthcare. I have zero trust in the US federal government to implement it properly. I think it would be a clusterfuck and make things worse for everyone, especially with Republicans on the warpath doing everything they can to sabotage it.

I'd argue we should give voice to actual libertarians instead of trashing them here.

Like, otherwise you at least don't help people find how actual libertarians respond.