Written and first recorded by Stephen Bishop (1985).
Hit version by Phil Collins & Marilyn Martin (US #1/MOR #1/CAN #1/UK #4/IRE #1/AUS #14 1985).
From the wiki: “‘Separate Lives’ was written and first recorded in 1985 by Stephen Bishop (‘On and On’, 1977; ‘It Might Be You’, 1982). Released only in Hong Kong by Polydor Records on Bishop’s vinyl LP, Sleeping with Girls (a cassette format would later be released in 1986 in the US and Canada), the song would be chosen to be used in the movie White Nights in 1985. Sung by Phil Collins and Marilyn Martin, ‘Separate Lives’ would reach #1 on the Billboard Hot 100 and Adult Contemporary charts as well as topping the charts in Canada and Ireland.
“Bishop received an Academy Award nomination in 1986 for Best Original Song, losing to Lionel Richie’s ‘Say You, Say Me’ from the same film.”