WELCOME to SR. You have found a GREAT place with lots and lots of Experience, Strength and Hope (ES&H).
I am glad you found us but sorry for the reason you had to.
Please look around and READ. There are some really good "Stickys" at the top of this forum with lots of good info.
I would like to suggest that you WAIT. This is not going to go away. Let his ACTIONS, not his words, show you over the next year how serious he is about recovery.
After his stint in Re Hab see if he is then willing to go to a Sober Living Home, where there will still be some rules, curfews, he will have to 'earn' privileges, etc and will be living with others in recovery, learning how to 'cope' in the real world without drugs.
To be honest, he is going to have a lot of WORK to do on himself and if he is serious about recovery will not have a lot of time for you for the first 4 to 6 months after rehab. This will give you time also to work on you, through counseling and the 12 steps of Nar Anon, figure out what your boundaries are (what is and is not acceptable) figure out how NOT to enable, etc
Just remember the 3 C's:
You didn't Cause this.
You can't Control this.
You can't Cure this.
I know this is a very frightening and confusing time for you. There are many on here who have been where you are, or are where you are. Please remember there are no 'guarantees' with an addict. As many that do find recovery and stay sober and clean, there are just as many and more that don't.
I was one of the lucky ones, I got sober and clean over 28 years ago, thought I was doing pretty darn good, and at 3 years was instructed by my AA sponsor to start attending Al-Anon (not for my AH, but for ME). It was a lot of hard work, and in some ways harder work, working on my 'codie' side than on my addiction side.
It will be a 'journey' for both of you and it will take time for you to figure out whether you want to do this journey with him or without him.
BTW if there are not that many Nar Anon meetings in your area or not at times that don't interfere with your work you can use Al-Anon also. There are usually many more Al-Anon meetings in an area than there are Nar Anon meetings, and the only thing I can figure out as to why is because Al-Anon is a much 'older' program than Nar Anon. Same steps, same principles.
Please keep posting and let us know how you are doing, as we do care very much.
Love and hugs,