Gilmour joined Pink Floyd in 1968, but as the years progressed, the two men were locked in a power struggle as their creative visions collided and, ultimately, Waters left the band in 1985.
Why did Pink Floyd fall apart?
Waters had left Pink Floyd to establish a solo career following the group's 1983 album The Final Cut, and considered his departure in 1985 to mark the end of the band. Gilmour and Mason disagreed, resulting in the final break in a badly frayed relationship.
Who ruined Pink Floyd?
David Gilmour Reveals How Roger Waters 'Ruined' Pink Floyd - AlternativeNation.net.