I have felt every single thing you describe, in relation to my stbx AH, although he never went to rehab or stopped drinking.
There is nothing wrong with your feelings, try not to feel quilty or ashamed of those feelings, they are natural to have. Anger that he couldn't do this whilst keeping up with his family responsibilities, worry about how you'll cope on your own during this period, profound sadness, fear about the changes that are coming, resentment that you have to keep holding everything together without intensive round the clock support that he is getting. I remember future-tripping about if my husband ever did choose to stop drinking, would he even want me anymore, as far as I could tell he had never even been sober for a full day whilst we knew each other, how would a sober him view me. you can feel all of these things and be very, very glad that he is making a positive change. Human beings are complex creatures.
Change and uncertainty can be very un-nerving, frightening.
Given that, if you are feeling overwhlmed by how you will cope practically, can you get some support for that? looking at your own situation, 30 days is not much time to adjust and work through your feelings, I found therapy very useful, depending on how old your little one is some therapists will let them be with you, some al-anon groups have sitter services or can help out with that. There will be people there who have been through your situation, and have felt every single thing you have felt, and will provide support and share strategies that helped them without judgement.
I can see you feel very alone, please try and grab the resources that are out there to help people in your situation, then whatever choices he makes about continuing sobriety, you will be in a better place to face the future and it's unknowns.
(((hugs)))