It depends on your intention and inner coherence. For most it’s symbolic as they are not fully in inner alignment to kill, and it’s not enough to overcome the will to live. You don’t have to visualize a death, you want to visualize a planet where she doesn’t exist, nobody talks about her, thinking about her, nobody remembers her, all is peaceful and crazy-girl free.
I would also recommend Furfur who can cloak you activities so she doesn’t divine this is happening.
If you have a good amount of anger, this video by E.A. from his old youtube details the ritual release of hatred in a baneful working. E.A. Koetting: 7 Steps of a Baneful Curse [Incl. Ritual Release of Hatred]
If that’s not enough anger to fuel this, but you still need to stop this person from trying to ruin your life, there’s a ritual to “stop your enemy’s feet” - also called the Chicken Feet curse - E.A. Koetting: The Most Evil Curse I've Ever Used (Adult Warning)
To use a freezerspell combined with a poppet to bind someone from working against you - Confused as F*** - #10 by Mulberry - and this can be adapted, if you stab the poppet to death, wrap it in a should and cremate it, all the while seeing it as dead, that’s one of the most direct death spells. Emotion amplifies this very well.