How to acclimate dad to change?

so if you've been keeping up with my ongoing drama with my Dad and the Adult Day Center, you know that I decided to abruptly pull Dad out.

So far, I've been getting by with telling Dad that he's just not going today, but he's starting to question why he's not going. To make matters worse, he thinks that he's done something wrong. He keeps attaching the driver yelling at him that last day (and leaving him) to thinking he did something wrong and that he's been kicked out.

I keep trying to assure him that everything is OK, but it's kinda stuck in his head that he somehow is responsible for being dismissed. I haven't had a chance to really dig into the issue since I'm on a work trip, but I feel AWFUL! I feel like I took something from Dad that keeps him happy.

Is there anything I can say or do to help him understand that this was NOT his fault? He sounds so sad ...