。
She still depends on her parents.
Literal
[topic-は] still parents [on-に] is-relying.
頼る ('rely on, depend on') here paired with まだ + ~ている gives 'is still in the state of relying.' The に marks the parents as the target of reliance — 親に頼る ('rely on parents') is a stock phrase. The implication can be evaluative: in Japanese as in many cultures, adult children still relying on their parents (especially financially) is a recognizable social pattern, sometimes labeled パラサイトシングル ('parasite single') in 1990s sociology — though the phrase was always more pejorative than descriptive. Without more context the sentence is mildly judgmental but not necessarily hostile.