Hi Rosie,
Yes they do, drugs and addictions are horrific things which effect more than just the addict – their families and the ones closest to them. There are support networks out there and you can speak to people who have been in similar situations to help you. They are called Family Friends, who have been there so do know more-or-less how you feel. You can contact them by dropping an email to info@icarustrust.org or you can go the website http://www.icarustrust.org. I really hope he manages to sort himself out for you, like he did before. As “CANT TAKE NO MORE” said, it is his fight.
All the best.