Take a look at what you wrote here. I think it is probably indicative of the types of thoughts you have looping around in your brain. You cannot change habits and negative behavior without changing your thoughts and emotions. I could explain the neuroscience behind that, but it would take a while. Suffice to say that the thoughts are set in a subconscious pattern that keeps looping and the loops then drive your behaviors and the choices you make.

It is extremely difficult to keep these kinds of thoughts from coming up. That takes a lot of meditative practice. However, you can learn to be more aware of them when they surface. You can learn to catch yourself and then then rewrite them so that you train your brain to end up in a new place of more beneficial thinking. Over time, the new destination will become the pattern when you are triggered.

For example, you said 'I will probably only make it one night without alcohol'. You can be on the lookout for these types of defeatist thoughts and then after they surface, think to yourself something like 'my old pattern has been to give in to this and buy alcohol. It is my will to stop drinking and I know I can go for as long as I want if I force myself to make better choices. I can do this'

'I'm a huge failure' can come up and then you can pair it with 'I have failed in the past and it hurts. I forgive and love myself anyway. We all make mistakes. I have had many successes in the past as well. I am going to be successful again.'

The goal is for your thoughts to end up in a different place each time. Pairing this up with feelings that shift from failure into self love and acceptance makes it even better. This type of approach serves to rewire your patterned thinking and emotions.