I have to echo LexieCat on the "been there done that" feeling. My husband did two failed stints at outpatient programs. When he went into rehab, I was cautiously optimistic. He's nearly 30 days sober and working a good recovery program and almost home from rehab, but I'm still just cautiously optimistic.
He's in an in-patient program, and we talk every day - at least once if not twice. He shares what he wants to with me - sometimes telling me funny stories, drama from other clients at the rehab center, what exercises he did in his therapy sessions, or just sharing that he's tired or had a hard day. I don't ask, I don't push. We're both introverted, although me much more so than him - I'm pretty textbook introvert...I get physically tired after any extended period of social interaction. But still we were able to sit with his counselors and talk - really TALK and communicate, which is something we haven't done in quite a long time. It's helpful for these conversations to be moderated and guided by professionals - they can help us keep things fair, on topic, and make suggestions about how we can get through rough spots. If/When you are ready - that is, when you're are detoxed and have started to work your recovery & are able to really focus - and if/when your partner is ready, maybe this is something you can look into to try to build a new base. I'm learning that we have to make a new norm and that I need to find myself and my footing in all this.
Still - while the much more open and honest communication between us is great & all, my husband understands now that it's his actions that will communicate loudest. Seeking treatment is a very loud and good communicative action. Sticking with it and working ongoing recovery is even better.
I wish you luck and success, and kudos for taking the steps towards sobriety & recovery.