What can you infer about Mary Shelley's personality based on this statement? Apex

In response to the statement from the introduction of Frankenstein " and as it will be confined to such topics as have connection with my authorship alone, I can scarely accuse myself a personal intrusion", this shows that Shelley was only comfortable talking about herself as far as her writing is concerned.

She was a very private person and only agreed to write the introduction as a glimpse into her life because she could decide how far of an 'intrusion' into her personal life she would make.