One less now.

but shooting someone that is holding a gun to another person's head seems very risky.

Maybe she’d practiced headshots. Some of the training goes over them.

Due to one active shooter who was wearing body armor and at least one of the people responding with a pistol was killed.

She knew the only realistic protection available is for her to take matters into her own hands to protect the family, herself and the boyfriend.
The police never arrive soon enough. All too often it ends badly for the woman.

Good for her. One less dirt bag.

Hesitating could have easily resulted in a very bad, alternative outcome.

Good for her. One less scumbag abusive asshole on this planet

of someone being put in such a position. This is traumatic for all involved and the apartment is a mess with blood and tissue splattered everywhere. The kids are going to remember this for a long time; the sounds the emotions and the smell of blood. It's the smell that lasts the longest and triggers the deepest trauma.

Why did the ex have access to a gun? It's not clear from the short article if he fit the profile but even if he were guilty of domestic abuse in the earlier relationship there isn't a mechanism for disarming a domestic abuser. Shouldn't there be?

Also keep in mind that in any given situation like this the woman is 5x more likely to be shot with her own gun than this 'happy' ending.

There ain't no way to put lipstick on this pig for anyone involved. Instead of celebrating death, however 'justified', we should work on preventing it.