Eveningstar,
BIG you are not failing as a mother. You are still learning about your girl, she's only so little and she's still learning about the world and herself. You are doing NOTHING wrong. You are the perfect mummy to your bubba and don't doubt that.
I agree with most of the people here in saying that I think that CC is not for me/us. My DH has been on at me to do it for ages, and I flat out refuse. I did it once and it was a disaster, I won't do it again.
I let her cry once (when she was about 6mths old) for about 5mins, not even that long and she power spewed everywhere. I was in tears, she was inconsolable and to top it off I had vomit everywhere that I had to clean up. It took me an hour to settle her down again after having to give her another bath, then I had to feed her again and get her back into her bed. I couldn't do CC even if she hadn't vomitted everywhere. I was outside the door listening to her scream knowing all she wanted was me and cuddles. It was heartbreaking. And I was sobbing my heart out making everything worse. When I went into her all I could do was apologise to her, saying 'mummy's sorry' over and over again, still crying, making her cry more. It was so traumatic for us both.
There are less traumatic, easier ways to do it. Babies are little for so little time. I would much rather cuddle her to sleep (even though she no longer fits on my lap...LOL!!!) than let her cry. I don't think that's teaching her anything other than mummy/daddy's not going to hug you when you're upset at night. Night time can be scary for little ones, as can being on their own, and trying to learn to control their bodys and doing what it wants them to.
I have had the tears of being so so tired and frustrated, I still do especially being pg and still waking 2-7 (yes 7!!!) times a night to my DD, some nights for hours at a time still. But I still cuddle her and give her a bottle if she wants one, regardless of what anyone else says. Yes I am tired and grumpy some days, but she is happy and lively and perfect and to me at the moment that's all that worries me. Even after a year, I am still learning about her.
Maybe your DD is teething? Even if there are no red gums or anything, the teeth might be moving under her gums. She's at the age where teeth start to move more now. That could explain the sleepless night. But don't let one night deter you. Keep trying and try to be consistent, you will find something that works. And remember you are doing your best, you can't do any more than that.