Does surviving violence make you a better person?

Maybe, though it also seems to impact dynamic decision making. Forthcoming in this month's American Economic Review:
Violent Conflict and Behavior: A Field Experiment in Burundi 
Voors, Maarten J., Eleonora E. M. Nillesen, Philip Verwimp, Erwin H. Bulte, Robert Lensink, and Daan P. Van Soest
Abstract: We use a series of field experiments in rural Burundi to examine the impact of exposure to conflict on social, risk, and time preferences. We find that conflict affects behavior: individuals exposed to violence display more altruistic behavior towards their neighbors, are more risk-seeking, and have higher discount rates. Large adverse shocks can thus alter savings and investments decisions, and potentially have long-run consequences—even if the shocks themselves are temporary.

A prior version of the paper is available here, repec here. Of note is this great opening line: "Civil wars are sometimes referred to as 'development in reverse'..."

That said, there is countervailing evidence...:
National Cultures and Soccer Violence 
Edward Miguel, Sebastián M. Saiegh and Shanker Satyanath
Can some acts of violence be explained by a society’s cultural norms?  Scholars have found it hard to empirically disentangle the effects of cultural norms, legal institutions, and poverty in driving violence. We address this problem by exploiting a natural experiment offered by the presence of thousands of international soccer (football) players in the European professional leagues. We find a strong relationship between the history  of civil conflict in a player’s home country and his propensity to behave violently on the soccer field, as measured by yellow and red cards. This link is robust to region fixed effects, country characteristics (e.g., rule of law, per capita income), player characteristics (e.g., age, field position, quality), outliers, and team fixed effects. Reinforcing our claim that we isolate cultures of violence rather than simple rule-breaking or something else entirely, there is no meaningful correlation between a player’s home country civil war history and performance measures not closely related to violent conduct.