From Longman Dictionary of Contemporary Englishlive together phrasal verbif people live together, they live in the same house and have a sexual relationship but are not married → live with They lived together for two years before they got married. → live→ See Verb table
Examples from the Corpus
live together• These days people often live together before getting married.• Al really wants us to live together, but I'm not sure I'm ready.• Anna taught her and made her her own maid and they lived together ever after. 