Hi Panther,
What are you imagining the outcome of the intervention as being?
What do you imagine happening if there is no intervention?
From my experience both with an alcoholic father (who is now 20+ years sober) and with during a four-year relationship with my alcoholic ex (who is still drinking), neither was ready until they were ready. Both abused alcohol as a way of self medicating and the roots of the alcoholism were indeed psychological.
I hope that your friend listens and takes the offering of help. He or she is lucky to have someone who cares so much.
Take what you like and leave the rest.