More gently put, staying with an active addict is like having a front row seat at a horror movie.
Sadly, addiction is a progressive disease and often gets worse long before they decide to seek help. Some do get help and find a better path, some spend much of their life in the revolving door of relapse/recovery and some never find help and end up in jail, insititutionalized or die. We never know what the outcome will be for the addict in our life.
The choice is yours, only you can decide what you are willing to allow in your life. Very few of us made good decisions early in the game, and we too had to learn the painful lessons in our own time.
12 Step meetings helped many of us regain our balance, I know they saved my life, literally. Alanon, Naranon and CoDA are three similar fellowships that can each help you more than you could ever know. Maybe look to see what is offered in your area and give them a try.
Hugs