。
She wanted to get divorced.
Literal
She [topic-は] divorce wanted-to-show.
~たがっていた uses the ~がる suffix, required when describing someone else's desire — the speaker cannot directly use ~たい for a third person. 離婚する (りこんする, 'to divorce') is a standard suru-verb. The がっていた indicates she was showing signs of wanting divorce over time.