It is an oversimplification, but there is a lot of evidence behind it. I suspect it's very unlikely for someone to fall into clinical depression from a quick breakup as in the article without something also being mechanically wrong. Fix that issue and they are likely to bounce back to a normal state like everyone else, with or without counseling. Depression is very nuanced and has many possible causes, but has high heritability and is very strongly associated with things like inflammation, nutritional deficiencies, and side effects of medication.
I wonder if this attack was facilitated by some security measures being relaxed to allow work from home.