Prescription Pain pill addiction help?

My mom had surgery on her wrist last year and was prescribed some pain pills. Now its a year later, and she takes 10 pills a day and if my dad doesn't want her, she says "my backs hurts" "my stomach hurts", Blah, blah, blah! She says that everything hurts on her and she just keeps eating these pills. To make it worse, she is buying them from a friend for $3 a pill.... She is bleeding us dry, she also drinks and smokes everyday! We don't know what to do, she threatens to leave the family if she doesn't get what she wants, We can't do that because we know if she leaves, her addiction will get worse and probably go to other more harmful drugs! I know we are enabling her, but if she didn't live with us, we KNOW she would eat as many as she could a day! Please provide advice... She doesn't think she has a problem. We just don't know what to do....=(