I appreciate it, it really is something worth investigating because it is a problem that affects the entire planet basically (looking at the amount of active users that social media have).
The most fundamental questions I could find are:
Loneliness occurs only in logical intelligent beings or also in animals?
Loneliness is something created by our mind or is it something physical like the lack of a resource such as water, food, air? (maybe some of our organs release some harmful chemical when we are alone for a long time, I don't know, something similar to adrenaline)
How long is the maximum time that a person spent alone and what symptoms did he present? (This could guide us if loneliness causes physical damage)
If loneliness does not cause physical damage, then do we do the damage ourselves? Why? Perhaps our sexual reproduction cycle is related to this? But then, Why do the elderly also suffer from loneliness if they have already passed their reproductive stage? And what about children?...
But the fundamental question:
Can someone survive alone? If the answer is yes, I immediately leave my city and go to live in the forest, it is not a joke.