Stopping a thought before it spirals

So I (22) have been attempting SR for the last 4 months. However, I’ve been struggling with changing my mindset and thoughts at times when I have the urge to release. I don’t want to deep down, but then the thought pops into my head randomly and then plays on repeat till I give in. Like I could be driving home from work and the minute I turn down my street the thought pops into my head and then within the hour of being home I end up releasing. The only upside is that I haven’t turned back to videos or images, I’m just with myself or in front of the mirror watching myself. Which does make me happy because I used to do PMO daily.

So my question is in those moments when you have that “1 second battle” what’re some ways you shut the thought down before it spirals and grows?