This all sounds good ie appropriate to the situation to me. How many times have I said, I can do it from here by myself? There should be a special name for this delusion, after me would be nice...

Don't take what he said about his leaving being neglectful, the wrong way. It's more like he's saying, he's in the middle of a heart transplant, he's taken yours out, he can't just stop now! Or if your manicurist stopped after one coat of color and told you to finish the job yourself. Okay, two ridiculous examples, but all three probably take more pride in the results of their work than the customer realizes (speaking as the manicurist!).

Good luck in the new school year.