Kelley, please go back and re-read Laurie6781's post. I couldn't have said it any better.
I was a hard-core needle user in my last years before rehab. I had plenty of labs done while in rehab, and I've had plenty since, including having blood drawn.
Yes, it was unsettling for me early on, but it
did not make me want to go back out and use. I wanted recovery more than anything else.
Anytime I felt "triggered" or had the urge, I had
plenty of people to call in recovery, including my sponsor, and I got past it.
These days I just feel ill when I have blood drawn. I've almost fainted a couple of times!
The world is full of temptations. It's up to him to figure out how he's going to deal with those.
Neither you or his father are going to be able to keep him in a cocoon.
Sending you hugs of support.
