I feel your pain. The worrying is what I hate the most. "just answer your phone and let me know you're ok" goes through my mind every day. Addicts feel ashamed about what they're doing ... Especially after a relapse. But they are also making the conscious decision to continue to use. They know what they are doing. It's very hard to deal with .... I try to take deep breaths and take a hot bath to get drowsy. Sleep is about all that cures my worry when he doesn't come home and is un reachable. I'm sorry you're going through this.
This board has helped me so much, and if you take the time to read around it will really help you too. The support here is amazing. Stay up, and be strong. Much love