dog peeing when in trouble

My dog is about 8ish months old now. Before I even say bad dog or NO or ANYTHING, she starts peeing on the ground & cowarding to the ground. I've never hit her. You can tell she knows when she does something bad (like tear up a pillow/blanket/couch pillow/etc). I can just look at her as soon as I get home, and bam she pees if she did something wrong, only if she tore something up.

I don't know what to do. Any ideas on how I would go about trying to get her to stop peeing? My vet has said it might possibly be signs of 'separation anxiety'. ..?

We do crate her 90% of the time when we are gone, but if it's for a short amount of time, we'll let her out for a hour or so alone. Most of the time she's a good dog, but it's just those few select times that she'll act out.

Thanks!