As far as I know, acute occurrences tend to be more intense (as experienced and reported in standardised tests) on average than chronic ones. Here, the risk of, e.g. suicide is also highest. However, long-term depression has a much more long-lasting impact on one's life, so I don't want to downplay it in any way.

Acute episodes tend to have a duration of only a few weeks or months so short-term therapy can be of great help here.

I agree that chronic depression requires long-term support. Your analogy with insulin and diabetes is excellent. And yes, the NHS falls short in this area, unfortunately. It would be great if more people could get the care they need and I hope it will become possible.

So yes, the NHS is not without its flaws. But considering the little funding it receives, it provides excellent care. It just shouldn't be so underfunded. I also think that it is also remarkably well-organised compared to other countries, e.g. Germany, where everything is much more bureaucratic and expensive. I also think it's significantly that countries with more privatised health care like the US.