As the above poster said, there are some things you can do. First of all, exercise. Everyone harps on it, and it's because it's really, really important. It does 3 things for you. First, it releases endorphins, which are the body's natural opiates. Endorphins help you feel better. If you start doing even 20 minutes of cardio a day, you'll notice the difference in how stable your emotions and thoughts start to get compared to now. Secondly, exercise will get you in shape, which makes everything about your body physically feel better. I used to be way out of shape when I was on opiates, and right afterwards I started working out with a lot of dedication. Within a month I had worked up some core muscles, and stood straighter, and I can't even describe to you how much better it has made everything in my life feel, it sounds silly but being strong and in shape physically feels SO much better. Lastly, if you're in shape, you feel better about yourself and more confident. Exercise truly is so important, if you're not doing it regularly, do it, you'll feel much better before you know it. It's hard at first but in a couple of weeks you'll like it. Join a gym, or the Y or something. Or if nothing else, run or bike every day and do pushups, etc. Look up exercises you can do to build strength, especially core strength, at home, if you can't or don't want to join a gym.
That should be the first step because it will help everything else. Besides that, you have to change your mindset. If you're sitting around not doing things that make you happy and thinking about how you're a "cunt" damaged drug abuser, you're going to feel like shit. Try to identify things in your life that make you stressed or unhappy, and try to remove or change those things if possible. Also think about what you like to do, what would make you feel good to do, and start doing those things. For me it was music. I had stopped playing music for 12 years, most of which I was addicted to opiates. I felt like that ship had sailed, and it had been so long I didn't even realize that it was a big hole in my life. After I got off opiates, I started playing music again and now it's the thing I focus on the most in life, it has given me so much joy and satisfaction.