The sole can get separated from the canvas without shrinking, simply because the glue softens with heat. That being said, your post is more believable after reading other comments that give more detail, like that the soles are likely made of Croc material, not rubber, and that you washed both your shoes and the large one in the pic is a new replacement.

Those details make a big difference for a couple of reasons. It explains why the tread on the smaller one looks much more worn (something that doesn't happen with shrinkage). And washing only one shoe indicates that it made it into the laundry by accident and if it was an accident and made of Croc material, it would have been highly noticeable and removed when transferring clothes to the dryer because the hot water actually stretches them and waterlogs the soles which would make them bigger and heavier. And if you had noticed and put it in the dryer anyway, you'd at least be aware that it's only the dry heat of the dryer that shrinks them, not the water temperature.

Anyway, wash your new shoes in room temperature water by hand and let air dry. Putting any kind of shoes in hot water or a hot dryer will damage them.

I think it was more like 'hey, you have the same kind of shoes I do, only smaller. Can I borrow one of them for a minute?' Canvas shrinks; rubber doesn't.

What I learned from therapy is that the point is to learn effective skills for coping with life's challenges. It won't fix all your problems but it'll teach you how to stop making them worse by behaving irrationally due to mental and emotional stress. With effective coping mechanisms, you can start building a life you feel is worth living.