Firstly Thanos is a psychopath.
Did thanos kill gamora. However Gamora never quite made it to Warlock as Drax the Destroyer intent on killing all things related to Thanos blew up her ship. Thanos had to sacrifice the one thing he loved Gamora. As Thanos seemingly died Gamora broke down crying.
He believes he loves Gamora but as she herself said This isnt love. It is pretty safe to assume Thanos killed him in his search for the power stone. Before Star-Lord could kill Gamora to prevent the knowledge of the Soul Stone falling into his hands Thanos captured Gamora and took her back to his ship.
After she fights alongside her sister Nebula Karen Gillan and all the women in the MCU in a powerful scene for the good guys during the big Thanos-ending battle Gamora is startlingly absent. Even for a galaxy that would presumably draw a LOT of attention. Thanos glanced in their direction and proceeded to throw Tivan in a specimen cage deciding to engage them personally.
Gamora attempts to finally kill Thanos. Love is not kidnapping a girl after killing her people forcing her to fight and torturing her with robotic upgrades when she fails nor is it forcing her to watch her adopted sister being tortured. Gamora dies and Thanos.
Thanos Was Lost Before Finding Gamora The new Thanos comic from Marvel makes Gamora more important than ever to his story and not the other way round. Who else does Thanos kill in Avengers. Discover 20 Questions and Answers from WikiLivre.
Despite taking a commanding lead in the Worlds Worst Dad competition Thanos apparently loves Gamora just enough to throw her over a cliff. In her comics origins there are a couple of different groups that are credited with killing Gamoras race. And secondly it seems to put more than a decade and as much as two between Thanos killing half of Gamoras planet and doing the same to Draxs.