Long term use of vicodin/ambien for elderly osteo patient

am 66 years old and have severe osteoarthritis and degenerative disc disease. About two years ago my Rheu. Dr. put me on Vicodin to be taken once in am and once in pm for pain and 5mg of ambien to sleep. Well I can honestly say it changed my life. I used to wake up at least 4-5 times a night with severe pain in my hands, hips and back. Now I sleep through the night and after I take my pill in the am I am able to perform many duties I had been able to do before. My question is will either of these medications used long term...I am presuming I will be on them the rest of my life..
contribute to memory loss, liver, or kidney (I only have one) problems, etc. I am definitely not an addicted personality. I don't drink, smoke or over eat. But then again I know they are addictive drugs and there could be a first time for everything and that is also intimidating to me. I do not want to be totally dependent on anything in which case one day I can not afford to purchase these medications. Thank you.