I need my assistant directors. I use them to mark down
every blocking decision, every important choice made, and any
note that is going to be important to the stage manager once
the play goes up. My job, as a director, is not reading the script
and writing notes during rehearsals - I'm not able to watch
rehearsal if I'm playing assistant director, and I'm not getting my
job done.

You have every right to be upset about the situation. It's a
deplorable way to treat a director - and, as a past director,
the person should know better.

Perhaps there are some territorial issues going on and the
person's lack of responsibility is a passive/aggressive way of
making a statement?

I've had the OPPOSITE trouble with assistants - LOL - when
they won't shut up and second guess my every decision. I think
I prefer your problems. LOL (not really).

That you have kept quiet so long is a testament to your
patience. If I were in the same situation, after two missed
rehearsals, the person would be replaced.

I have always held a policy that if you aren't having fun you aren't doing it right. Almost everyone involved in community theater has a full time job, family etc. I have made it completely okay if someone volunteers for something then finds that they can't do it. I certainly don't want to work with someone who doesn't want to be there, or doesn't have the time to be there. That isn't any fun for anyone. In your case I would have told the past director/assistant director that you realized they had too much going on outside the show and that you really needed someone who could be there to assist you. No hard feelings. Maybe you can work together again sometime. (Then you decide if you want to work with them again if they ask you.)Then I would have found someone who was willing to do the job. It sounds like you did fine with a great cast and script, so enjoy the rest of the process.

Good luck with your opening.

Linda 

Sometimes egos get in the way. I had this happen with one of my plays. The person I chose as my assistant director had a ton of experience throughout the country doing theater in a number of areas. I felt like this was a person who could add a lot to our theater and even had some experience in bigger theater. However, this person quickly began to question everything we did, etc. Unfortunately, while I liked this person very much, we were forced to remove them from the production. To make a long story short, the play went off without a hitch and was one of our biggest money makers ever. Just keep this in mind, you have paid your dues. You have been an assistant for a long time and you know what you are doing. This is YOUR play and it will have your name on it. Your assistant has made a choice. I would say something to them and find out what their interest level is and in polite way mention that when you were an assistant you tried to help the director and expect the same curiosity. If they have a problem with it, I would officially remove them as my assistant director and if you had any intentions of putting them in your program, posters, etc. I would kindly remove them.

Edit:  On reflection, this post is way too long, mainly pointless, and kind of stupid.  Just read the stuff in blue below and ignore the rest, ok?

My directing mentor told me that father told him, never be an assistant anything.

He told me this on a production where he was assistant director.

Some years later, he made me his assistant director.  I still don't know if that said more about me, him, the theatre, or what.

My reason for telling these seemingly pointless facts is this:

Nobody knows what an assistant director does. 

When I AD'd for Cat On A Hot Tin Roof, I directed the Gooper / Mae scenes, from the ground up.  When I AD'd for a David Ives one-act, I came in and doctored scenes where the director needed help.  When I AD'd for Here We Come Gathering, I handled all the blocking, because the director couldn't.   On other shows, I've seen ADs basically direct the show, act as SM, fetch coffee, and/or sit around and look pretty.

The point - there's a point?  Yes, yes, I'm COMING to it!  The POINT is, the director and AD MUST agree BEFORE auditions on exactly what the AD is supposed to do. 

Now, Director99 made the very reasonable assumption that the AD would do just what Director99 had done when the roles were reversed.  And it blew up in Director99's face.  All you can do now is do without the AD.

I've had situations, in and out of theatre, where my job was very strictly defined.  Push Button A when Light X comes on.  I can do that.  I'm not all that happy with it, but I can do it.

I've had other situations where I've been given lots of rope.  Go ahead, POB, do what you want, in areas A, B, and C, just don't touch E or F.  Oh, boy!  Like that a lot.  I can do that too.

But what I can't deal with, is when nobody tells me where the line is.  I'm your AD.  What should I do?  "Just help me all you can." I'm all enthusiastic, so I draw up a rehearsal schedule.  Whoops, SM is doing that.  Okay, I'll give the cast some warmups.  "Nobody talks to the actors but me!"  Well, sorry.  What CAN I do again?  "Just be my assistant.  And you're doing a pretty lousy job so far, because you haven't DONE anything."  Fine.  I'll do something.  I quit.

I'm not saying this is what happened to Director99.  What I think happened there is, somebody's ego couldn't deal with the role reversal.  What I AM saying is, it's as easy to get in trouble by "going over and above what ADs usually do" as it is by doing nothing.

The lines need to be drawn, far, far before auditions.

Had a really nice post here, but the board ate it.

NO, it was NOT your fault; the other director violated a standard that you had set up by past practice between you.

I was more addressing the situation where the director and AD HAVEN'T worked together before.  Let's say Debbie Director is doing a new musical version of "Scream Blacula Scream", with a cast of 72, plus bats, and has two choices for AD: POB and Director99.  She tells us the AD's job will be "the usual stuff."  Two weeks after auditions, it becomes apparent that the AD is expected to fill the blood capsules, play second trombone in the big "Bite Me" number, and comb the fleas out of the bats.

Director99 may say, "Great, I'll help any way I can", because Director99 is a true theatre trouper and a great human being, and will go take trombone lessons and buy a bat comb.  POB, having no musical talent, a morbid fear of fake blood, and an allergy to fleas, will strangle Debbie and then quit.

If Debbie had been explicit about what she wanted, she could have hired Director99 and avoided a miserable death.

In your situation, you and the AD KNEW what to expect from each other, because you'd been there before.  That's great, except that your AD apparently decided to go ego-trip on you.   Next time, or in someone else's situation, the AD may have no idea what the director wants.

That's what I was talking about.  Sorry if I wasn't clear.  I'm often not.

Best of luck with the show; with your obvious talents, I'm sure everything will be great.