sndman, Been in your shoes and know the turmoil your are going through. My girls were 11 & 14 when I began my decent. The guilt used to kill me and after I got clean I used to agonize over what I had done. My wife is very very close to the girls and she has told me that the girls are fine, they new what was going on but they see me know and they know there old Dad is back and the kids these days are fairly flexible given what they see and experience in school and outside school. To help me get over the past I look at it as a chapter in my life, I'm completed the chapter and move on to new wonderful chapters. I had a chapter when I was in high school, one when I was in college, one for my 20's years, 30 years, etc... Each chapter lived and closed out. I move on and now make each new chapter the very best it can be, work hard not to repeat mistakes and as I've said before, like most things in life you have to work at them they just don't happen so I work hard to never ever abuse drugs again. Hope that helps, but I think you will be fine and your son will be fine also, just stay on your new path and crate new memories with him, he'll warm up and accept the new you as the norm.
Hope that helps
phil