First recorded by Jimmy Clanton (1965).
Also recorded by Ruth Lewis (1966), The Walker Brothers (1966).
Hit versions by Chad Allan & The Expressions (CAN #19 1965), Ruby & The Romantics (US #113 1969), The Carpenters (US #2/MOR #1/CAN #2/AUS #4/NZ #7/JPN #56 1972).
From the wiki: “The earliest version of the song was recorded by Jimmy Clanton, the singer from New Orleans known as the ‘swamp pop R&B teenage idol’, in February 1965, produced by the song authors, Gary Geld and Peter Udell. He rode the crest of the popular teen music wave in the 1950s and 1960s. Seven of his records, including ‘Go, Jimmy, Go’, ‘Just a Dream’, and ‘Venus in Blue Jeans‘, charted in the U.S. Top 40.
“Chad Allan & The Expressions, from whom The Guess Who would later evolve (Randy Bachman, Jim Kale and Garry Peterson were original members; Burton Cummings replaced Allan in 1966), also recorded the song in 1965 on their Canadian LP Hey Ho (What You Do to Me) … teasingly subtited ‘Guess Who?’. Released as a single, ‘Hurting Each Other’ hit #19 on the Canadian charts in early 1966. In June 1966, a version by Ruth Lewis, produced again by the song’s writers, Geld and Udell, was released as a single by RCA Victor records without any apparent chart impact. A cover of ‘Hurting Each Other’ also appeared on The Walker Brothers’ second album, Portrait, which was released in November 1966 but their recording was not released as a single. However, ‘Hurting Each Other’ was the final single released by Ruby & The Romantics (‘Hey There, Lonely Girl‘) before the group’s break-up in 1969 and, even though it ‘Bubbled Under the Hot 100’, it was the first appearance of the song on a US music chart.