I'll take a stab at this.
1) What techniques do you use to stop worry?
Worry for me is a useless emotion, and generally indicates that I am trying to control something that isn't mine to control. If I feel worry, I ask myself: "is there an action I can take to positively change the outcome?" If so, I take it. If not, I let it go.
2) How do you stay in the now and prevent worrying about future expected bad scenarios?
See above. In addition, I make a real effort each day to focus on the present. The past is gone and the future cannot be predicted.
3) How do you combat negative thoughts?
I have goals in my life. I run my own business and have financial goals. I am learning Spanish (I speak French and some German) and plan to live in various South American countries for several months each once I have accomplished my business goals. If I find myself in a negative space, I go out for a long walk, or I meditate and bring myself back to my priorities.
4) How do you shut off concern for the alcoholic/addict's health and well-being? (What do you tell yourself that helps you?)
Notice that my above goals aren't focused on other people. I don't allow people into my life who will interfere with me reaching my goals. This includes addicts and alcoholics. I don't use drugs and I rarely drink. I make no apologies for this, and I don't have much tolerance for people who limit their potential by using substances. What has helped me most in my recovery is to focus on ME. It may sound egocentric, but I am doing no good to the world when I am miserable because I am hung up on other peoples' problems.
5) How do you enjoy your life, your food, your health, your warmth, when you know your loved one is suffering and you "should" not "help" them (because helping hasn't helped them)?
My loved ones will do what they choose to do. If they sink, I don't have to sink with them. In my view, Self-sacrifice is a flaw, not a virtue.
6) How do you make decisions that you are sure are morally sound (such as "not helping")?
What do you consider to be "helping?" If I have money, I might consider helping to pay for rehab, but just once. I will not sit and listen to someone's sob stories, or do for others what they can do for themselves. And I absolutely will not allow myself to be abused. I don't care if the loved one is "sick." That is a line that they will not cross with me, or I will take immediate action to get them out of my life.
7) When you get "bad news" how do you handle it?
I say a short prayer, and ask God to handle it appropriately and with mercy. Then I put my focus back onto myself. What will be will be. I do not control the outcomes of other people's actions.
8) How do you make sense of your loved one being alcoholic/addict and evidently not learning from the horrible experiences that has brought (i.e., jail, hospitalization - almost dying, etc.)?
Experience is the best teacher there is. If someone in my life, no matter how much I love them, cannot learn from experience, then they certainly aren't going to learn anything useful from me, no matter how much effort I put into it.
I accept that I will never understand even half of what goes through the heads of my family members, friends or business associates. I have a hard enough time understanding myself most of the time!
But ultimately, the people in my life have their own paths to walk. As do I. I'm in my 50s, and my thoughts on all this are very different than they were when I was younger. But the older I get, the more I appreciate that the world is set up this way.
Thanks for posing these questions. By answering them, I can see how far I've come in my own happiness.