。
She's loved by everyone.
Literal
[topic-は] everyone [by-に] is-loved.
愛される is the passive of 愛する ('to love'); the resulting state 愛されている ('is loved' as an ongoing state) describes a stable property — being beloved. The passive here serves a topic-management function rather than backgrounding the agent: it lets the woman remain the topic of the sentence even though the action of loving is done by 'everyone.' 愛する is a Sino-Japanese verb of slightly elevated register — for everyday romantic 'love' Japanese tends toward 大好き ('really like'), 好き ('like, love'), or 恋する ('to fall in love with'). 愛する covers deeper, more enduring affection — family, lasting partners, abstract objects of love (one's country, art).