How long does your elegy need to be? That might help determine what you need to include. Keep in mind that an elegy is a poem; so if your elegy does not have standard meter or rhyme, at least try to give it a lyrical (songlike) quality. What you might want to do is divide your elegy into four-line stanzas. In the first, you could discuss Portia as a wife to Brutus; in the second, you could describe Portia as a Stoic, and in the last stanza, you could discuss who will miss her and why (especially since her husband does not seem to mourn her death much).
One other suggestion, I would write the elegy from Cassius's point of view. He is Portia's brother and demonstrates much more grief over the news of Portia's death than does her own husband.
Portia is the very humble and obedient wife of Brutus. However, since Brutus is also a conspirator who is under a lot mental stress because of his plans to assassinate Caesar his relationship with his wife is strained and tense. The obvious reason being he cannot reveal and discuss the finer details of the conspiracy with his innocent wife Portia. This tension is palpable in Act II when Portia on bended knee begs of her husband to know the reason why he has not slept that night. Brutus offers evasive replies, and fortunately for him Ligarius, whom he had sent for, is heard knocking at his door. Brutus hurriedly asks Portia to leave saying that he will reveal everything to her later, "and by and by thy bosom shall partake/The secrets of my heart...Leave me with haste." And she being the obedient wife does so.
After Caesar's assassination and the consequent civil war, Brutus is fully involved in public affairs and circumstances force him to completely ignore his wife with tragic consequences. In Act IV sc.3, Brutus tells Cassius how pitiably she died. Brutus tells Cassius that Portia died by swallowing hot coals. Since Brutus had been away on his military campaign and on hearing that Octavius had joined forces with Antony, she had become very upset and mentally distracted. When she was left unattended she swallowed hot coals of fire and died:I
"Impatient of my absence,
And grief that young Octavius with Mark Antony
Have made themselves so strong:--for with her death
That tidings came;--with this she fell distract,
And, her attendants absent, swallow'd fire."
To conclude, Portia is important inasmuch as she reveals more of the personality of Brutus than about herself.
i ment how i could use it in an elegy ?? sorry