Sorry to hear you're having a tough time, mate.
Two of the biggest things I've come to realize are:
1. Control is illusory.
2. Learning to let go can save your life.
What I'd recommend is, as Mr Peabody suggests, taking some time away from any and all substances for the moment, and using that time to look at your life and what it is that causes you to feel such dissatisfaction. I know the feeling horrendously well, but I also know that trying to fight with it, change it, or make it into something it's not will only lead to more problems. Sit with those thoughts and emotions without trying to change them, leave them as they are and just observe them; look at the thoughts that come up with certain physical sensations, or how certain emotional responses happen every time you think of, for example, someone who you believe wronged you in your life. The more you look at these patterns of mental and physical sensations, the easier it gets to recognize them and let them go before they can interfere with your everyday activities.
It's as simple as recognizing them, not ignoring or repressing them, just acknowledge them and let them go. They
will pass away, they
will change, they are
not "you" and do not imply a "you" who is experiencing them or causing them to be there. I can promise with, with completely certainty, that those feelings, although they may seem to, do not remain static and are in a continual state of flux; use this to your advantage, learn how futile it is to hold onto the unpleasantness and see how ridiculous it is to allow such transient, empty mental objects, which is all they are really, dictate how you will feel about life.
Whether you believe in reincarnation or not, we only have
this moment right here in which to be truly alive and so it makes no sense to allow what
might happen next, or what's already happened, to spoil it.
I hope you sort your head out soon, and that you find something of use in this post.
When it blows, it stacks...