If you haven't already guessed, this article has MAJOR SPOILERS for Marvel's "Avengers: Infinity War" regarding major character death. Now that you're informed, let's jump in.
Marvel's third installment of the "Avengers" series takes a dark turn, wiping out half of their universe in a less than five-minute sequence.
Today, out of all of those deaths we're focusing on Peter Quill's reaction to Gamora's Death.
Gamora is one of six Guardians of the Galaxy. She is a Zehoberei who was "adopted" (adopted is a loose term) by the villain of this installment in the series. Thanos, her "adoptive" father kidnaps Gamora from the other Guardians of the Galaxy because he knows that she is aware of where one of the Infinity Stones is located. When she finally is forced to give up the location of the Infinity Stone, this stone being the Soul Stone, Thanos brings her along. It is revealed that in order for Thanos to retrieve the stone, he must give up the soul of someone he loves, ie. a soul for a soul. This soul that he gives up is Gamora.
Peter and Gamora have been officially intimate since the second installment of the Guardians of the Galaxy movie, "Guardians of the Galaxy Vol. 2." being referred to throughout the movie as an "unspoken thing". At the beginning of the movie, the year is 1980 and when we return to the Guardians in 'present time', it is told to us that it is 34 years later, making the year 2014. "Infinity War" takes place in the year 2018. Even by now, the relationship isn't confirmed as much more than a "long-term booty-call" according to Quill. The I love yous exchanged by the couple prior to Gamora's kidnapping tell us that there is more to their relationship than that, though.
When it is revealed that Thanos killed Gamora and Peter Quill loses his cool, causing the teams efforts of removing the gauntlet to crumble and Thanos to retrieve the last two Infinity Stones. Many people are comparing Quill's response to that of Drax the Destroyer. Thanos killed Drax's wife and daughter and he wants nothing more than to be able to kill Thanos with his own hands. At the beginning of the movie, we see Mantis put Drax to sleep in order to keep him from lashing out against Thanos. Peter later does this same thing upon learning of Gamora's death.
Peter is going through the stages of grief at this moment. This is a normal human reaction to the death of a partner. At this moment, we can see Peter briefly go through the first stage of denial when he converses back and forth with Thanos, asking for a confirmation of her death. Once her death is confirmed, we can see the second stage, which is anger. Peter is more angry at himself at this moment. One of the examples of anger stage of grief is being angry at yourself for what you did or failed to do, whether it is real or imagined.
Peter Quill's reaction to Gamora's death is real and human. There was no way that anyone would be able to contain themselves after learning that the person right before them murdered their loved one. The person before you hurt someone who you loved so dearly and you in that moment can do something about it. Peter Quill lashed out, yes, but in all reality can you really blame him?