With effects of PTSD in soldiers only recently be treated seriously, how was PTSD in medieval times? Was it worse?

On my phone so a bit briefer than I'd otherwise be.

This may be a better topic for a psychology subreddit. But basically, while combat stress reactions (and stress reactions in general) are a universal human response, the form those reactions take is not universal. If you read symptomatic presentations of shell shock, battle fatigue, PTSD, etc there are significant differences (especially normatively and statistically; with large enough pools of afflicted individuals, just about any specific reaction can be found).

Now, what's really interesting is that the reaction to the stress is shaped by personal expectations. As in, if you expect to react a certain way when overcome by the stress of war and combat, you generally will. There is, or at least was a quiet policy in the UK for Afghanistan/Iraq wat veterans. Specifically, not to call their stress reaction PTSD unless they were already strongly presenting as such. So, while a similar proportion of returning vets had combat stress reactions compared to those in the US, the majority drank lots of beer in pubs, with only a fraction falling prey to the less functional PTSD reaction. The social element of beer fueled alcoholism was considered preferrable by the NHS (national health service) both to make it more likely someone would catch a vet who was closer to the edge, as well as improving odds of psychological recovery.

I'm interested to see if any studies will come out in a year or two about the effect of an extremely popular show called Bodyguard, where the protagonist (a vet) struggles with suicidal thoughts. But I'm digressing. With that kind of lens, it partially explains some of the kamikaze behavior of the Japanese in WW2 (including suicidal infantry charges by exhausted units), some berserker activity, etc.

So, were there stress reactions? Almost certainly. But they probably didn't look like PTSD.

Beyond that, war was less constant. They didn't have IEDs, snipers, long range artillery, bombers, etc. They marched (a lot) and had the occasional battle. But the stress and risk of death was much less constant. In fact, up until the era of modern medicine, disease typically claimed more casualties (at war) than the enemy did, but these were deaths the population was used to enduring (average life expectancy of 25 years in 17th century France, for example). Sieges, with the risk of epidemic and a more aggressive operational tempo may have been more difficult to endure, which may have contributed to the vicious sacking of cities taken by storm rather than surrender.

Also remember that depending on the era, the troops were feudal. They fought for a few months, then returned home where they had a lot of support. Compare that to modern deployments which can last much longer.

Overall, I'd expect different reactions, often at a lower frequency compared to modern warfare, but for there still to be a number of individuals with stress reactions to combat.