There is a whole lot going on here with your friend. He either has a characterological disorder ("Personality Disorder"), a thought disorder (like schizophrenia or an associated diagnosis), or both... it/they may be organic or drug induced - it is (of course) impossible to diagnose over the internet, but here is the botXXXXX XXXXXne: forget about "reason" or "logic" for the meantime, as he is beginning to spin into a world of his own. The paranoia in particular concerns me, as his behavior may become more volatile as he descends deeper into a paranoid state. I would urge you to get him to the doctor before he decides that doctors are no longer to be trusted, and my instinct tells me that the window is closing fast. Medication and therapy can definitely take the edge off of the delusions and some of the erratic behavior, but he has to (1) attend an evaluation, and (2) comply with treatment (i.e., take his medication).
If you still have enough leverage, or clout, with him, use whatever you can to schedule and attend the initial evaluation. I would also recommend a psychiatrist over a general practitioner. I do not know the laws in your country, but in the USA, we cannot force a person to seek treatment over the age of 18 unless they are a direct threat to themselves or somebody else. Your friend falls through the cracks (for the time being - be careful in the long run) because he is not currently a threat, but he is clearly in need of treatment. If you are satisfied with the response, please hit "Accept." That is the only way I can receive credit for my answer. Thanks-
Watch your back, okay? When the paranoia takes over, reality bends for these folks and they are liable to do anything. So plug away for as long as you feel safe, and then disconnect for self protection. But seriously, good luck. I can tell that you really care about him.