me when I accidentally say "Toyota 1983–1985 Sprinter Trueno GT-APEX" instead of "you" when she asks what I'm thinking about

I don't know what happened or if this applies to you but trying to ignore and forget something often makes it stick around even more persistently, that's one way PTSD can develop sometimes. Taking the time to think about it and process it is healthier in the long run once you come to terms with it.