Fear is a powerful thing. As a mother of a 23 year old, addicted son, I know the fear you speak of. I also know that I cannot live my life in constant fear...it is not healthy for me as a person.
I know that I did not cause my sons addiction, I can't control it and I can't cure it. This has been a gift that I have learned in my own recovery. It has made a large difference in my life.
On down days, I sink into dreaming...thinking about what a sweet, loving child my son was. Thinking about all the dreams and plans I had for his future. I still struggle with this. But, I always return to reality...he is an adult making choices for his life. I can't put him in time out and hope he learned his lesson anymore. I always knew being a mother was the hardest, most rewarding job I would ever have. I just never expected this.
I remind myself that I did everything I could to raise my son to the best of my abilities. While he is still my son, my baby, he is also a grown man. Realizing that I cannot save him, I cannot fix the choices he makes has been HUGE for me.
Keep coming back. The folks here have been such a blessing to me, as I am sure they will for you. I wish you peace.