I'm thinking of burning the one existing copy of her life's work.
Why would you burn something like that of someone elses?
I don't think it is worth saving.
Destroying something meaningful, or something that is another person's property is wrong and hurtful. It's important to consider how you may feel if these actions were taken against you.
I don't care. She really needs to get over herself.
It's important to consider how your actions toward another person will impact them, and others. Hurtful and negative actions toward others will only lead to consequences for yourself.