Discouraged

[danshe]

I've been knitting for about 6 months and loving it. My main problem is that I can't fix mistakes. I've both read and been shown how to unravel or unknit but my attempts lead to a complete mess. I put one scarf away unrepaired several weeks ago waiting until I can get the hang of it.
But I'm 2/3 done with this noro scarf and decided to give it a try: http://www.oceanwindknits.ca/section...ree%20patterns

My only option is to rip it out and start again- but there's no guarantee I won't make a mistake again.
Can one be a "knitter" if she can't undo mistakes?