Earlier quoted context omitted.
Why do you think that she wouldn't have tried to commit suicide via another means if she didn't have access to a gun?
If I understand correctly, plenty of research shows that it's an impulsive decision, and access to a tool that makes it easy greatly increases the likelihood of acting on it. The research shows that the presence of guns, in particular, in increases suicide. Killing yourself is hard; a gun makes it a push-button operation. However, it would be much better if someone could share the actual research with us.
As a PSA, don't ever try to kill yourself with a gun. The success rate is only 70 percent. The 30 percent who survive are much worse off than the rare jumper who survives the golden gate bridge