Continuing relationship after rehab

Hi All,

My boyfriend of 2.5 years just entered rehab for 30 days to recover from his prescription drug addiction. We are both in our twenties, and I had a close relationship with his parents. There was some codependency in my relationship with him, probably because I am an adult child of alcoholics. I have been to therapy for about a year to work on my issues associated with this, but it did not stop me from having the same behaviors in my romantic relationship. His parents are now very angry with me for not telling them that their son was doing drugs and putting himself in danger. Do you think this is right on their part? Was it my responsibility to tell them before he did himself? Do you think that codependent relationships can be cured by the addict "fixing" their problem?

Thank you and I appreciate any input.