。
Her attitude toward me was different from usual.
Literal
She [topic-は] me [toward-に対する] attitude [subject-が] usual [from-と] was-different.
~に対する is the noun-modifying form of the compound particle ~に対して — the ~る ending is the attributive form, allowing it to modify 態度 directly. Compared with the simpler に, ~に対する/~に対して emphasizes orientation or stance toward something, often in formal or evaluative contexts: 私に対する態度 = 'attitude oriented toward me.' Inside the topic-comment frame, the topic 彼女は is the global frame, and a smaller subject 態度が picks out what specifically was different — a typical 'big subject, small subject' structure.