The analyses of a text #3

The narrator recalls his adolescence.
He visited his old friend Traddles' place for the first time, and there met his old friend Mr. Micawber as Traddles' land lord who had been a debtor quite a while.
And he invited Taddles and the Micawbers to his apartment.
Now Mrs. Micawber is grumbling to him about her husband's unstable job.

'I will not,' said Mrs. Micawber, finishing her punch, and gathering her scarf about her shoulders, preparatory to her withdrawal to my bedroom: 'I will not protract these remarks on the subject of Mr. Micawber's pecuniary affairs. At your fireside, my dear Mr. Copperfield, and in the presence of Mr. Traddles, who, though not so old a friend, is quite one of ourselves, I could not refrain from making you acquainted with the course I advise Mr. Micawber to take. I feel that the time is arrived when Mr. Micawber should exert himself and - I will add - assert himself, and it appears to me that these are the means. I am aware that I am merely a female, and that a masculine judgement is usually considered more competent to the discussion of such questions; still I must not forget that, when I lived at home with my papa and mama, my papa was in the habit of saying, "Emma's form is fragile, but her grasp of a subject is inferior to none." That my papa was too partial, I well know; but that he was an observer of character in some degree, my duty and my reason equally forbid me to doubt.'
[David Copperfield by Charles Dickens]
1. I'd like to know what "at your fireside" means.
2. I'd like to know why it is "to the discussion," not "in the discussion."
3. And I'd like to know if three"that" clauses in blue are the objects of "know."
Thank you in advance for your help.