New Behavior:
There are three different variables involved now:
- DTEMisMelancholic / DTEMisNervousWreck
- DTEMmelancholicTrait / DTEMnervousWreckTrait
- DTEMrecentlyConsumedAntidepressants / DTEMrecentlyConsumedBetaBlockers

I will explain it with Melancholic but basically same behavior for Nervous Wreck
EveryHour the game will check if DTEMisMelancholic is true, if it is true it will also check the value for DTEMrecentlyConsumedAntidepressants
If DTEMrecentlyConsumedAntidepressants equals 0 (which means the player haven't consumed antidepressants) the value for DTEMmelancholicTrait will increase by 1. When the value for DTEMmelancholicTrait is above 0, the "Melancholic" trait is given to the player. DTEMmelancholicTrait can stack up to 720 (which means 30 days).
If DTEMrecentlyConsumedAntidepressants is higher than 0, means the player took a pill, so the opposite will happen, DTEMmelancholicTrait will be reduced by 1. When the value for DTEMmelancholicTrait is lower than 0, the "Melancholic" trait is removed.
So, What's completely new? DTEMmelancholicTrait can decrease up to -720 (30 days), if the value reaches that number, then, the flag DTEMisMelancholic is set to false, which means, the trait is permanently removed. (DTEMmelancholicTrait value will be set to 0 for future if the trait is adquired again).
So, you may be wondering how DTEMrecentlyConsumedAntidepressants value changes. When taking a pill, the value is set to 72, every hour, that value will decrease by 1 until reaching 0, so this means that the check of "recently consumed an antidepressant" will last for 3 entire days. Additional to that, the consumption will also reduce DTEMmelancholicTrait value by 48, so this means that each pill will grant 5 days full of progress towards removing the trait.
Being able to obtain the trait (if didn't pick at the start) remaings the same. After the first 7 days of survival, if the Unhappiness moodle is present, a roll occur which basically is: hoursSurvived / moodleLevel, and then a random number is picked between 0 and the result of the division, if that random number is 0, the flag DTEMisMelancholic is set to true.
So, the higher amount of time you survive and the lower you keep the unhappiness moodle, the less chances of obtaining the trait.
It is still "quite" easy to obtain it at the beginning if you don't take care of it (there's plenty of books, magazines, comics, etc now), but now you can work to permanently remove it. And in late game, after you removed it, it is very unlikely that it is added again as you will be AT LEAST one month and a week of survival, which translates to a lot of hours, which translates to the roll being less powerful.