That last part, about spending some time apart is dead on. Which is why her one to three week trips to Mexico have been okay, because exactly what you said happens and does happen. The heart grows fonder, seemingly big things are seen for what they are—not so big a deal in the grand scheme of things.
Much more than that, though, and it's too much.
I would say it probably depends on where you go to school and what you major in. Some things, I think formal education is indispensable. You need it in order to get on a good footing, knowledge, experience, etc.
Other things, you might learn better on the job, in an apprenticeship or the like, such as in the vocations—electrician, plumbing, etc, or even in a lot of the technology fields because you're learning something like a proprietary coding language or specialized process anyway.
In my case, I knew a lot about Social Media Marketing before I went, just by doing it for my books. I did learn some things at school, and I did get to create stuff I probably wouldn't have tried on my own.
The thing about education, especially higher education, that most people get wrong is that it's not really about getting knowledge. Sure, you learn stuff, but you can do that in a public library, the most important thing is to learn how to think, retrieve knowledge and apply it.
Having raw knowledge today is IMHO useless, I have a college at my work that is filled with info on just about everything, actually I was his boss for a while. He was actually called to be a star at the national TV station on some kind of a quiz. So this guy knows just about everything on any given subject - he's basically Google. But he's stupid, he can't do shit on his own. You have to explain every thing that needs to be done, and then recheck 5 times to see what he did wrong. In the end, I got tired of holding his hand all of the time and I've fired him (from the project) - I realized I don't need another Google.
The practical vocations - it's basically the same thing. Yes, you learn from the experience but the people who were actually apprenticed by masters who explained not just how but also why, tend to be much better at their job. Because only if you understand why something has to be done in a certain way can you go ahead and think of a better/efficient/faster way it can be done. And that is what a master of any craft or vocation really is - someone who can do things better, faster and efficient than us other guys.
I'm guessing that most people get the critical thinking wrong about education in general because it doesn't happen as often as it should. Instead of being taught how to think (which is something I would hope would happen at home and in every day experience of life, too), students are being taught want to think. Like your Google Man who is a fountain of knowledge but has no clue what to do with it.
So, when the majority of the professors in most universities (I'll keep it to the US though it's got to happen elsewhere) are teaching their own findings and theories as truths, or primary and secondary teachers are teaching from carefully selected and approved texts so that students can pass the standardized one size fits all tests, those students who actually do use critical thinking skills end up castigated for questioning what's being taught or why it's being taught.