Your friend is wrong, either because she has been mislead or because she is a genocide denier. Attempting to paint the Srebrenica genocide as a "both-sided" affair is a common tactic of genocide deniers. This most commonly involves drawing false equivalence between the Srebrenica Genocide of July 1995 and events which occurred during the two and a half year Siege of Srebrenica - itself an atrocity for which the Republika Srpska bears full responsibility, but in which Bosniak military forces were also involved and also committed war-crimes. Forces of the Republika Srpska murdered eight thousand people in cold blood, at the culmination of a two and a half year siege of a humanitarian refuge during which some thousands more had died.

To answer your questioning of "it was a war. During war, people die," it's important to understand that the Srebrenica Genocide was not a battle. It was not two groups of armed combatants waging war. It was one group of armed combatants - soldiers of the Republika Srpska, overrunning a humanitarian refuge, systematically sorting the men and boys in that refuge from the women and girls while also committing wanton acts of rape and random violence, corralling the men and boys - unarmed civilians - into groups, and then machine-gunning them en-masse. This was followed by a systematic cover-up of the atrocities. Your friend's complaint is akin to someone complaining that nobody thinks of the concentration camp guards on International Holocaust Remembrance Day.

You may be interested in a more in-depth overview of the Siege of Srebrenica and the Srebrenica Genocide. If you'd like to learn more, I'd encourage you to have a look at this discussion here.