Hi Peo, you're not alone. I can remember when my ex alcoholic husband of 20+ years sent me a text message that he was leaving me while I was having breakfast with a family friend. I hadn't told anyone what horrors were happening in my home and at that moment I burst into tears over my meal and had to explain for our mutual friend that my husband has been a raging alcoholic for many years and had just left me. It was so embarrassing to tell my friend he was choosing booze over the family. I was devastated. What a waste of years.
Unbeknownst to me, he gave me a gift in his leaving. I grieved the loss but with time I found peace in my life and you will eventually too. There is no price that can be put on having peace and peace of mind.
The disbelief and high emotions are too raw for you right now to see the hidden blessing in his packing up and leaving. I know that sounds rough, but imagine your son being taken to a school event and your husband driving your beloved son to it while drunk. Yes, this is a real possibility if it hasn't happened to you and your son already, not to mention all of the potential possibilities that could happen because he drives wasted. It happened to my children and the fear they had was tremendous. The shame I feel because I didn't catch it has never gone away. There are so many worse things that could happen other than your alcoholic husband leaving you that can't be undone, so let him leave.
Get help via Al-Anon and counseling so this isn't repeated in your life. You can build a home for you and your son on a strong foundation FREE of addiction and it's misery.
Peace and hugs to you.