。
She broke the vase on purpose just to upset me.
Literal
She [topic-は] me [object-を] cause-trouble-to [in order to-ために] deliberately vase [object-を] broke.
Two notable points. First, 困らせる is the causative of 困る ('to be in trouble, be at a loss') — '(she) made me distressed.' The causative ~せる/~させる on emotion-state verbs creates 'cause to feel X' meanings (喜ばせる 'make happy,' 怒らせる 'make angry,' 泣かせる 'make cry'). Second, わざと is the adverb for 'deliberately, on purpose, with intent' — usually carrying a malicious or mischievous nuance. Compare with わざわざ ('going out of one's way to'), which often suggests considerate effort. The pair ~ために plus わざと together makes the spite unmistakable.