Hi Nick
The dark night can be tough, but stick with it it's just a passing phase. Don't stop practising

In regards to your comment about the coke, here's a quote from MCTB which might be relevant:
"The illusion of satisfactoriness has to do with the false sense that continuing to mentally create the illusion of a separate, permanent self will be satisfactory or helpful, and is not referring to some oppressive and fun-denying angst trip"
Here's some stuff to play around with which might make it easier. Firstly, a lot of suffering is amplified by negative thinking. Mindfulness of thinking can be an extremely useful practise. Try being extremely alert watching for the next thought, like a cat watching a mouse hole. Try to also be alert to the subtle, under-the-surface thoughts. The more subtle the thought, the easier it is to identify with it. I found recently that I'd been identifying with subtle negative commentary and judgements. Here's an excellent article about it:
http://www.shinzen.org/shinsub3/artEmptyMind.htm
Negative emotions can be divided into their component parts to make them more manageable. For example, you may find that negative emotions are made up two components which are bundled together: thoughts and physical sensations.
If you find yourself really caught up in it, one thing you can experiment with is taking a third-person perspective and be the witness to your experience. Step back and see yourself, "Oh there I am thinking negative thoughts, feeling restless, feeling dissatisfaction." This can be useful to break yourself out the small self if you're rly stuck.
Another thing which makes the journey more pleasant / bearable is metta practise. Of course you need to make sure you don't identify with those thoughts and judgements that may come up e.g. "This is superficial, inauthentic" etc.
- Martin