My thought is that five months is not very long. If he truly means he wants recovery, five months will be a short amount of time. It will. You need this time to focus on yourself. If it is meant to be it will be after he recovers. If you intervene you will become way too involved. It is not wrong to suggest Alanon, but I do think it is wrong to set up how many meetings. What one person gets out of six meetings can be quite different for another person. I dont think setting five months is realistic either as in reality it takes so much longer.
Someone who is suffering and is in recovery does go through this. Anguish and depression is part of the recovery for almost everyone I have spoken to, and there have been many. I let my husband return to our family immediately after rehab. What a mistake. Although he has been clean since April, I have went through his ups and downs in addition to mine, and it is a mistake. I did it for my children (10 and 4). Having him gone was so hard on them I could not imagine how it would be if he stayed away. In reality, it would have been ok and I could have worked on myself more so than I have. It has been a long and hard road and honestly I should have been concentrating on myself and my girls and said to him come back after you have been clean for a long period of time and worked through all the BS.
Being clean is only the first step. They have to have their regrets and deal with where they are in life then figure out why they were self medicating in the first place. It's a long haul if they truly do it, and that is a big if. Not trying to discourage, it is just honesty.
Stay strong and give yourself this time. It will be the best thing you ever do for yourself and it will test the strength of your relationship and if he means he will do anything or if he is just saying what you want to hear right now. Rehabilitation is hard and most addicts would rather have someone there supporting them so they dont have to face doing it on their own. Unfortunately, only they alone can cure themselves.
Good Luck and God Bless!