Job thanks for the reminder on not asking him to do anything, and Peace for the reminder to keep expectations very low. I would not have roped him into a parenting talk, except that S was with him when I discovered the school issue and I was afraid they would head off to a movie or something, leaving S no time to do the current homework, much less the past due. I definitely gave him an out in terms of coming or participating. I was surprised that he did come knowing there would be a difficult discussion because about 6 weeks ago he wouldn't even get off the freeway when he drove right by our house to see S when I asked him to because S was self-harming heading into his finals (and at that point he hadn't seen S in a while). He pretty much supported my approach regarding S's schoolwork and expectations and he displayed a lot of empathy and affection toward S. He reiterated to S that he was not mad at him, that he understood the struggles, and he gave S a very warm hug when he left.
It occurred to me later that the texting could have been work-related (he always had a lot of that in the evenings regarding patient loads, overnight instructions, etc.) or could even have been a means to test me to see how I would react (I remember Happy Again's threads in the efforts he took to test his W to see if she had really changed). In the past I would have told him not to do it in front of me or in my house. I didn't care who he was texting and I think I made that obvious through my actions (or lack thereof). I could also see him, having appeased me by putting his phone face down, determined to show me that I couldn't control his behavior. I also think he was texting when S left the room, so probably a way to put a barrier between us and handle his anxiety in case I might try to bring up the separation agreement.
In terms of him rushing off, it was 8 pm by then, with an hour drive back to where he lives. He may have also wanted to leave so that S could get his work done. Will never know one way or another, but I should probably stop assuming the worst of him all the time.
I hate to say this but I personally have no hope for OD to ever go to counseling, and I don't have a lot of faith in counselors myself so I doubt that I would even encourage it at this point. I've been to quite a few now, and I did not personally have any revelations there that were any better or more helpful than simply reading well-reviewed books on the various topics.
I plan to not initiate any contact with him for at least a month, when I will have to contact him to get signatures for our taxes. In all, there was some definite pulling back in communication and eye contact, but positives too. He showed up, he demonstrated empathy, he helped to problem solve, he didn't run from a difficult conversation, he was cooperative with me in communication and coming, and he didn't say anything too snarky.