I understand what your saying...my H gave me something from his recovery class that I keep in mind...it said this:
No one will ever understand the extent and amount of guilt that the recovering alcoholic feels inside.
I will try and come across some things that I have found helpful reading...maybe in time you can ask that she "look them over" because no matter what happens with you two you will forever be contected with your son...and for that reason alone it best that she understand fully what you are dealing with...because your son has the potential to follow in your footsteps...he has a greater risk of becoming an alcoholic himself...I am sure she would want to understand all she can for his sake...now may not be the right time...but in time you two will need to discuss this...
I also believe you when you say that you never wanted to cause her the pain and hurt you have...I don't believe my H did either...it was such a relief to me when he finally realized what he was doing and was able to get help...I hope, given the time, your wife will feel that relief as well...just give her time...and yourself time...you need to heal as individuals...then you can move on from there...
Take care...and don't worry 'bout crying in front of me...it only makes you a human!