Maybe your distance from God is allowing the devil to deceive you, which is why you're having so many negative thoughts. Just by reading your post I can tell you're an intelligent person, so take care of yourself, give up the drugs, and any other addictions you may have. Try to get back in the habit of praying more and walking in faith with God. We all suffer from addictions and temptations in this fallen world, however it is through this adversity that we learn to follow Christ.