When I was in your friends headspace.. through alcohol not meth... the greatest help for me were the people who advised or truly listened but who had strong boundaries.. I dont mean tough love.. but they were people who really cared but who I knew I couldnt manipulate... it came down to one good friend, and 2 AA members ..they didnt judge me for still drinking, but they did support me for trying...and kept giving me 'hints' on where to be and really listened..