How to Feel Better About Work Situation

I work as a curriculum specialist in a school district. This summer was particularly challenging as we normally get two weeks of vacation time in the summer to regroup from the school year, but this summer the unwritten expectation was that even when we were off, we were “on.”
This past week I took a few days to be with my family and completely disconnect from work because I was on the verge of serious burnout.
While I was out my boss sent us a number of emails requiring time sensitive responses which I did not get to because I really needed to disconnect; I chose to disconnect.
He sent an email today that contained a sentence thanking those who responded even while on vacation. I felt like it was a jab at me. Meanwhile, some others took off 2-3 weeks in July to be at the beach while I worked my tail off but that didn’t seem to matter. I am trying to change my thoughts regarding the email, which are currently: I should have checked my email; now I look like a total slacker, while I’ve been busting my butt and ignoring my kids all summer. I’m such an idiot. I should learn how to play this damn game, but I don’t want to. (I know that’s many thoughts). Essentially I want to feel excited about going to work, be able to support my teachers whole-heartedly without feeling guilty about taking time to fill my cup. I’m having a hard time finding a more useful thought and navigating my workplace.