Did Roman soldiers (when the Roman empire was around) suffer from psychological problems after going to war?
Of course they did, or we can assume they did, just like soldiers of any other epoch. Roman soldiers were only human. We know at times they panicked. It is true that their culture emphasized stoicism in the face of adversity. That didn’t mean they were immune to trauma, just more likely to suppress it. One major problem is that Roman historians appear to have been constrained by censorship, particularly in the difficult periods in which trauma was most likely or widespread. They sometimes had to omit mention of defeats–if they heard of them at all–or other things not conducive to state propaganda aims like maintaining good morale. Since stories of psychological problems stemming from war were likely to hurt recruiting and public morale, they didn’t or couldn’t mention them.