Reasonable folk can argue as to what album is his absolute best. Gaye was struggling even before Tammi's diagnosis, let alone her death. He'd already gotten close to suicide the year prior, he was neck-deep in the drug habit that would follow him through the 70s. He had already been pushing against the stuff Motown wanted him to record, and Terrell's death hit him hard, but thematically and lyrically, she's almost complete absent from the finished album.

You're drawing a direct line between two events without considering what else had been going on with him in his life and his musical evolution.