Yep.If he gets arrested or needs money desperately, perhaps to pay off a fine or a drug dealer, he'll call you. If he is like most of our difficult children, he will not call you to ask you how you are, just to chat about life with YOU, or to wish you a Happy Birthday. Most difficult children do have some things in common. The ones we talk about here, with a very few exceptions, think we exist only to give them stuff or to rescue when out of trouble, even if they ar 45 years old.
Don't feel like it's personal. It is usually a part of their personality or because of their drug abuse. It is very hard to accept what our grown children are, but when it is in our face, there is little choice.
You however can take good care of yourself and give yourself a party of a day, if you want one. I would try to be very good to myself if I were you and to stop hoping for something you know will only be bad news (a phone call from difficult child). If you have other kdis or a SO make plans with them. Or call a friend. Or do something you love to do, but don't do often enough. This is the first day of the rest of YOUR life, and it matters A LOT. You can't change your difficult child...none of us can...but we can enjoy our own lives and do everything we love and make a difference in the world. We do not have to feel badly all the time because one of our chldren is not doing well by his own choice.
Lots and lots of hugs and wishing you a hapyp, serene day 
