I've been through this. You two have to create some sort of hand shake or ritual to do as to reset both of yourselves together back into a corruption free, tension free, free environment. Its about creating peace and keeping peace.
If they stay clean I suppose so. So much as they see that using and being in a relationship is tough been there. I found that the relationship with drugs always was the one us addicts loved more then we could love each other...
No.... But if she is serious about quitting... Drink plenty of Frozen Orange Juice while taking Vitamin C Tablets. See a Doctor about getting on Ibogaine... it has been working miracles as an Anti Addiction Drug for Heroine Addiction...