Hello craff - Just about anyone who reads your post has been there
I really hope you can push through this one, you would be so happy if you did. Knitting can be such a rewarding experience.
I agree with salmon, if you can spot the error, you may be able to avoid ripping the whole thing out.
At any point when you were knitting this, were you able to complete the pattern and then have the two stitches at the end? If so, this would most likely be where you need to rip back to.
Using stitch markers would be very helpful, I would say perhaps every 3 to 4 pattern repeats. This way, if you make a mistake it would be pretty easy to catch it, and you wouldn't need to go very far back to repair it.
Hope this helps.