I think I would tell someone who is plagued by addiction and who really wants to change, that there is indeed a life beyond the despair of addiction. In my case at least, this requires a leap of faith and really listening to those who have successfully embraced a new, whole life. This is one of the reasons I find SR to be so wonderful. Real life people from all walks of life who have done the hard work and are able to show us the way.
Just plod along, day by day. It does get better.
Good luck!