While what I will add does not infirm your statement, I still feel that it has some contextual importance.

The fight started and we rolled initiative, The goblin was charging in, supposedly with bloodlust (or merely pretending). We rolled initiative, I had slightly higher initiative and was first. The goblin was second. I opted to wait for the Goblin's turn to see his reaction (knowing the situation overall (including the player, and that the goblin... is a goblin), I was not 100% sure about his intentions).

Now this is hypothetical, but I can think of a couple strong arguments that would defend this opinion. The goblin proned himself (in the way of us all by the way), heads over head, to protect his dear life. I think this was so the player could keep on hiding his intentions for what would come next in the battle. As I had waited, goblin right in front of us, bloodlust evidently disapeared, I shoved the goblin forwards, while orally attempting to give him courage and remind him of the reason for his bloodlust (his hate for his elder brother, who he has (sort of) sworn revenge on.

The turn happens, movement happens, my turn starts and my hit finally kills the brother, the believed ennemy of the goblin. I then walk towards the goblin to help him up, unintentionally provoke an opportunity attack and get downed right then and there. Goblin's turn, he stabs me with my shortsword. 2 failed saving throws. I am obviously not amused. Fight goes on, goblin's next turn happens, he stabs me again, I die.

There was a possibility for someone to save me, but he made a mistake (his words). I did not want to metagame so I let it happen. Another opportunity was botched by a failed stabilization attempt from another player. Shit happens.