As a mother, you will probably always worry about your son, that is a natural, normal, and healthy emotion.

You did not say how old your son is, and that is certainly an important  piece of information.  If he is still a teenager, 18 or 19 then I can see this level of worry for him to be out on his own for the first time (which causese parents to worry enough) and adding addiction problems to this scenario just makes it worse of course.

However, if he is well into his 20's or even 30's then his not contacting you is not really reason to worry.  Many young men of this age are struggling for independence, and one way in which some accomplish this is an emtional distancing from their parents, and some need to do this through establishing a physical distance.

If there is a history of addiction, than there are other scenarios going on as well.  Your son may have relapsed once again and feel ashamed, and not want you to know all of the terrible details up close and personal.  This is especially true perhaps if you are a very emotional sort of mother, always giving him a lot of grief and drama for his addiction (nagging).  He may be waiting until he has acheived a certain period of sobriety before contacting you, so he can make you proud and happy, rather than fearful, stressed, anxiety ridden, and angry.

If and when he contacts you perhaps you can try to avoid any dramatic scenes of confrontations.  Don't ask him about his addiction or his progress, just treat him as if "nothing is wrong" so that he is not anxiety ridden to contact you about anything, fearing a dramatic confrontation about his recovery.  Make contacting you as stress and guilt FREE as possible if you want him to stay in regular contact with you.  Just be as cheerful and happy as possible and don't ask any questions other than the general conversation questions you may ask a friend  you run into on the street.

This may be VERY difficult for  you at first, it may even feel like you are beign superficial or phony.  But you have to work at it.  Adult children need to be treated as such by their parents, or they may assert their adulthood by making a choice not to associate with people who they feel disrespect them, even if those people are their parents.

This are just my impressions upon reading your post, a lot depends on your overall relationship with your son, before the addiction problems.  Some parents and children are just not emotionally close, and don't have that much in common so when the chidlren are grown, they just begin to establish their own life and don't make as much time to keep in touch with the parents.  I know this is the case with my husband.  He was never close to his parents when he was a kid and teen, they were always working and just did not forge a true bond with him.  He was the oldest and they had other children, whom they spent most of their attention on, and my husband felt lost in the shuffle.  When he was 18 and went away to college, he just started to live his own life and did not make time to stay in touch with his parents.  His parents love him, and his emotional distance causes them concern, hurt, and worry, and they have expressed that to me, but my husband just says that they never made time for him when he was a kid, so he does not have that much time for them now.  No anomosity, more like indifference.  I think this is because his parents respect his feelings and don't try to push themselves on him, or pry into his life.  If they were pushy and demanding, I am sure my husband would sever all ties with them.  But, since they try to be respectful about his feelings, when they call or come over my husband will always kindly spend a few mintues with them, he does not ignore them, although he won't initiate contact.

It is hard to know what to say to your post, since there are so many variables.  Such as, does your son have a job?  How highly does he function with his addiction?  Is he married or in a stable relationship with someone who may take care of him if he is unable to function due to his addiction?  And his age and educational level.

As a mother of a grown child I certainly sympathize with your sitaution and  sincerely hope that your son is doing well and contacts you soon.

Isabela