、。
She was so sad that she didn't want to talk to anyone.
Literal
She [topic-は] very sad-was [because-ので], anyone [to-にも] talk-to-want-not-was.
誰にも~ない pairs the indeterminate pronoun 誰 ('who') with にも ('even/to as well') and a negative verb to mean 'not to anyone, no one at all.' Same skeleton powers なにも~ない (nothing), どこにも~ない (nowhere), いつも~ない (never). 話しかける is a compound — 話す (speak) + かける (cast, direct toward) — for actively addressing or initiating speech with someone, distinct from just 話す (speak in general).