I am part of a world wide tech savvy subculture. Last year a guy who is part on that sub culture had some drama with his ex in Germany. The guy is a scrawny little man, ex marine, american. I needed a dogsitter, and he agreed to come over, watch my dog and use my Dutch apartment for a few weeks while I was off to San Francisco.

While I was off he made a bit of a mess. He drank heavily and caused some minor ruckus with my neighbors. But we got along somewhat well and I actually worried a tiny bit about him, so I fed him, gave him stuff, my friends gave him clothes.

We had some minor accidents. After taking LSD he got an epileptic seizure. Also he didn't really take good care of himself, and didn't wash properly. He also drank excessive beer, and you could smell it in the hallway.

So a month later I had to travel again, this time for a book project. I left for a month to Africa, and he was pissed off and visibly envious. I suggested he start paying rent, since clearly he didn't have any place to go and was in a bad state medically. He agreed with a reasonable reimbursement for full use of my place.

I returned ahead of schedule. I stayed away 8 weeks, we bartered for 3 months. When I returned there were some minor accidents. My dog was in a neurotic state, and had chewed up my couch. The guy had been drinking excessively and the house stank like an open sewer and he had been extremely rude to neighbors. His behavior was severely off and he was clearly suffering from extreme depression. I agreed to let him stay till after the hollydays but indicated we would have to end this arrangement. I had no confidence I would get any of the money he had agreed on paying for what was now well in excess of three months staying there, full use of my appartment and internet.

So mid january the situation blew up. I asked him to leave and he kept adding days. So on a specific evening when he had promised to be gone by sundown and he straggled in drunk an stoned and highly agitated. I had cleared out his room, and demanded he leave within the hour. He became vicious, muttering and abusive. A friend witnessed this and was shocked. After she left he became spitfaced angry at me and I exploded. I really got angry and threw his stuff out.

This is a year ago. Since then he has been spreading some rumors about me. We had momentary contact just now and .. I can only qualify his attitude as delusional and extremely hateful. He actually hates my guts down to the core. Like as if I am not a human being. I am positive he wants me to suffer pain for his misfortune and the way I saw him - using drugs, sick, vulnerable, drinking heavily, depressed, just a very messed up human being.

Turns out he contacted my ex, or someone very close to her, and he told me a deeply distressing story that is a very painful misrepresentation of something that happened more than ten years ago. He actually went out of his way to discuss things with people in my private sphere. Might be one of several people, but can actually be my ex. These are people I am no longer on speaking terms with for completely different reasons.

The degree in which he viciously tried attacking, humiliating me is uncanny. My default response is ignoring him, but clearly that may not be a fully safe course of action. We just had a conversation on FB chat just an hour ago, and while at the start of the evening I didn't feel anything about this man, he went out of his way to push my buttons and I feel vaguely agitated and annoyed.

What can I do? What should I do, other than completely ignore him? The guy received a huge inheritance since then and he might be inclined ... to use this money to harm me. He is that kind of a wretched human being. I'd qualify him as completely insane, of the dangerous kind. I am sure given a chance he'd torture and murder me. His hatred is so viciously outrageous, it is on par with bad cinema.

Did I lead him on? Not much. I am good at expressing contempt and I made clear I want nothing to do with him. I may have expressed some cold insults, which did nothing to assuage his already boiling temperament.