My mom is 72, has had EVERY test known, is perfectly healthy, but refuses to participate in life!!!!

My mom has what the doctors call "IBS". Although she has had literally every test in the world done to her, the doctors cannot find anything wrong with her physically. She's been told by her doctors to eat more healthily, get some exercise, quit drinking so much coffee, and quit smoking and if she does these things she will feel better. She REFUSES!!! She wants a magic pill to cure her ills. She pops Vicodin like candy, (52 in ten days just recently!!) and then complains that it's her IBS having an "attack". Her doctors have tried putting her on anti-depressents numerous times but, she freaks out and says she's not depressed and wishes everyone would quit trying to tell her that she is. She insists that she is always in pain. This has been going on for years and it's only getting worse. We finally figured it all out this past summer. She had contracted the Tetanus infection over the summer and nearly died. She was in a medically induced coma for five weeks and in the hospital for three months total. While this was tragic and horrible at the time, she has recovered fully. While in rehab she was given only Tylenol for pain and as soon as she overheard the nurse tell her it was time for her Tylenol she flipped and insisted she needed her Vicodin that it was the only thing that would help. She takes it for every little ache or pain and won't believe us when we tell her that it is destroying her intestinal system and that THAT is why her stomach hurts all the time. Along with the fact that she barely eats anything, drinks coffee all day, has a glass a milk or two, and gets ZERO exercise. My brother and I have had it with her whining and moaning and groaning. She is the only one who can fix this but, won't listen. Now she is always upset with us because "we don't understand the pain she is in" and "we never come see her or help her". I live over 75 miles away, own my own business, have two kids, and am a single mom. My brother lives quite close to her, but her and his wife have their own lives too. She is perfectly capable of doing everything on her own but, refuses to do it. She wants us to do everything for her and we just can't. She won't socialize, exercise, cook, or do anything at all. She can't stand this person or that person so we can't get her to go to bingo or play cards. She complains that she is just worn out. We don't know what else to do. I told her that if she can't care for herself or her house then she is going to have to sell it and move to an assited living facility. Well, that just made her more mad at me for not understanding her. She hates the world, hates the people in it, is addicted to CNN and all the bad stuff of the world and can't understand why we don't share her views. I give up and so does my brother. What do we do?????