I found arming myself with knowledge about addiction was the best thing I could do to help me cope, also I belong to a local support group.
I have stood by one family member who clearly wanted to stop; he got himself into support groups, attends online training on how to manage his addiction and has been clean for over eight months, he did relapse several times, but he’s now doing a mental health course as he has identified that his mental health issues led him to take drugs
Another family member, I paid for a months rehab, sadly he refused the ongoing support and was back on cocaine within a month, it’s a hard battle to stop addiction but it can happen, I used to enable him by giving him a home and money, he knows I love him but he now lives in a hostel, as I can’t cope with his lies and the chaotic lifestyle he lives.
Separation is not the only option there is lots of help out there, we went to our GP who was really helpful
Good Luck