The analyses of a text #3

The narrator recalls his adolescence.
He is beginning a new life as an apprentice in Doctors' Commons at London.
He visited his old friend Agnes's lodging at her invitation after work.
Now She talks to him about a certain change of relationship between her farther and his apprentice Uriah.
They talked about a lawyer her father's strange changes several months ago.

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"You remember our last conversation about Papa? It was not long after that?not more than two or three days?when he gave me the first intimation of what I tell you. It was sad to see him struggling between his desire to represent it to me as a matter of choice on his part, and his inability to conceal it was forced upon him. I felt very sorry."
"Force upon him, Agnes! Who forces it upon him?"
"Uriah," she replied, after a moment's hesitation, "has made himself indispensable to Papa. He is subtle and watchful. He has mastered Papa's weaknesses, fostered them, and taken advantage of them, until?to say all that I mean in a word, Trotwood?until Papa is afraid of him."
[David Copperfield by Charles Dickens]
1. I'd like to know if "it" refers to "when" clause.
2. I'd like to know if "his inability" indicates his anxiety made him tell her the truth.
3. And I'd like to know if "to say all that I mean in a word" means "if I say all that I mean in a word."
Thank you in advance for your help.