In my 20th year I can report that I've seen some relationships go the distance when one person is in recovery and the other is a non-alcoholic. As "seekingcalm" said, both have to be very serious about their own recovery and be willing to work like a demon to change and grow.
But an active alcoholic or addict is incapable of having a relationship with anything, anyone other than the bottle. As the alcoholic sinks he/she pulls the other person down.