Although I really hated HSC English (because it compulsorily counted towards the ATAR and most of it was not useful), I found the analysis skills involved to be occasionally useful - for example, when you're watching a movie or playing a story-driven game. You're never expected to be able to do this (unless you choose to study a B Arts), but it's nice to be able to recognise those little details and you really do get a bit more out of the movie/game/whatever.
It's a shame that for most people the course didn't actually involve much analysis at all - most of it was looking up techniques for <insert text here> and cramming quotes and paragraphs. I found the texts really hard to get into as well.
The ATAR isn't really the ultimate goal of high school. It's more like an intermediate step, but it (understandably) gets blown way out of proportion during the HSC because of all the stress involved. The ATAR has exactly one purpose, which is for unis to make the selection process more manageable.
You will almost certainly forget about the ATAR once at uni, because there's no place for it there - you have people coming from different countries, different education systems. The only thing that you could possibly be compared on is your performance at uni.
My English study was writing at most one essay per term and making a half-effort to memorise it in the week before exams. I ended up with crappy marks and was a half-mark away from a band 4 but my ATAR was good enough without it, and there's no reason for me to ever care about it again.
Don't give up. Just try to hold on. If you get the ATAR you need, great. Even if you don't, just pick something else and transfer as soon as they let you. Not a big deal either way.