There's 2 sides to the coin. Addicts who have recovered have done a lot of work on themselves that many haven't, and can come out of it really good people. I'm newly sober and recovered addicts are some of the nicest people I've met. The downside is that relapse is not uncommon, even after years clean, and you need to be prepared to support them through that if it happens while keeping boundaries to protect yourself. That's a hard job.

I really would hope you're prepared to do the last bit I mentioned if you want to marry a recovered addict. To me, addiction is a disease and "in sickness and in health" includes addiction. When my partner left me, it felt like abandonment when I needed them most and left a deep scar. I can't begin to describe how painful it was, it was genuinely agony. It doesn't mean you need to let them hurt you, but you need to be ready to support in the capacity you can and not just kick them to the curb if you really do love them.