Welcome to SR Lori
I know how you feel... I left my husband in April and he told me a few days ago that he started an outpatient treatment. He told me he was going to do group therapy twice a week and will be going to AA three times a week. We haven't had much contact since I left and I was glad to hear that he might be on the right path now. BUT my first thoughts were: he's only doing group (?), he really should have a individual therapy session at least once a week... does he know he needs to work the steps at AA and not just show up... I should tell him that he needs to find a sponsor asap... - Instead of saying any of this, I took a deep breath and told myself that he will do what he will do... his treatment/ recovery is something HE needs to deal with and I need to make sure that I don't obsess about his every move because then I'm right back in all that craziness. I told him that I hope his treatment is going well and left it at that. Just like I couldn't control whether he drinks, I can't control the treatment program he chooses or doesn't choose. It's hard, I know, but you will feel a lot saner if you try to concentrate on yourself and let your husband focus on HIS recovery.
I completely understand what you mean when you say you don't think that your marriage can handle a relapse at this point. But you can't prevent a relapse by controling your husbands every move... maybe try channeling all that energy into something you HAVE control over - YOURSELF! Figure out what it is you want in life - what can you live with and what are you no longer willing to live with... that way IF your RAH has a relapse you know what you need to do for yourself!