The analyses of a text #5

The narrator recalls his adolescence.
Peggotty, the narator's old nurse's niece Em'ly fled with the narrator's best friend Steerforth to somewhere on the day when Peggotty's husband's funeral was held , leaving her fiance, her cousin Ham.
Mr. Peggotty, Peggoty's elder brother came to London with the narrator to seek for his niece the day after next.
Mr. Peggotty told him to arrange for him to meet Steerforth' mother and he wrote her a letter for the appointment.
And they visited Steerforth's house the next day and now Mr. Peggotty is talking to Steerforth's mother.

Here "he" refers to Steerforth.

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Again Rosa Dartle tried to soothe her; again ineffectually.
'I say, Rosa, not a word! If he can stake his all upon the lightest object, I can stake my all upon a greater purpose. Let him go where he will, with the means that my love has secured to him! Does he think to reduce me by long absence? He knows his mother very little if he does. Let him put away his whim now, and he is welcome back. Let him not put her away now, and he never shall come near me, living or dying, while I can raise my hand to make a sign against it, unless, being rid of her for ever, he comes humbly to me and begs for my forgiveness. This is my right. This is the acknowledgement I WILL HAVE. This is the separation that there is between us! And is this,' she added, looking at her visitor with the proud intolerant air with which she had begun, 'no injury?'
[David Copperfield by Charles Dickens]
1. I'd like to know what "I say, Rosa, not a word!" means.
2. I'd like to know what "has secured to him" means.
3. And I'd like to know if "after" is implied before "being."
Thank you in advance for your help.