So, I was given some advice for situations like this that changed my life.
The first thing that comes to mind in these moments isn’t what matters. It’s what a life time of indoctrinated racism/classism/sexism etc looks like. The thing that comes to mind here isn’t necessarily what you think, it’s what you’ve been taught to think,
What matters is what you do next, after the thought has popped in to your mind.
I was raised in a very racist environment, and I struggled with feeling guilt every time some racist thought I’d been trained with popped in to my head, because that’s not the person I want to be. Reframing it like this allowed me to stop getting hung up on the guilt part, and work on the part that actually means something