"Plan to get married and have a family"
Before I'd consider the above, I would become more knowlegable about addiction.
Addicts lie, addicts deflect and less than 10% recover for life. In addition, children of addicts have a 50% chance of inheriting the gene that predisposes them to addiction.
Knowledge is power, there is more to his story. Read all the stickeys at the top of this forum, and others posts, lots of good information at your fingertips.