Y'know what I resent most? Being guilt-tripped.

I won't mention any names, but it's happened to me several times within the past couple years. Here's how it plays out:- A stranger, whose name I've only ever seen from browsing FA, asks me to draw somethings for them. I politely decline, but rather than to accept No for an answer, they start making passive-aggressive remarks about how I'm selfish, and that nobody else cares for them, etc. etc. Which, as a sensitive person, causes me to hastily apologise to them, out of fear of being hated. I succumb to allowing myself to add them on Skype/Telegram to try and make it up to them. They take advantage of my caring nature and start to say/do some really rather fucked-up shit; sexually RP-ing with me and my characters and trying to become my "boyfriend". By that point I'm stuck in a situation where the only way I can give them the message that they are making me extremely uncomfortable, is to tell them to fuck off and block them altogether. After that, they chew me out thru a PM and then forever hate my guts. And that's that, they are out of my life but I'm even worse off than before I'd ever met them. They've successfully made me beleieve as tho' I am a bad person. Again, this has happened on more than one occasion.

What should I do? Am I truly a bad person?

TL;DR -- Please don't use me just to get free arts, thanks.

EDiT:- Also, it should be mentioned that this Journal was not intended as putting anybody on blast, nor do I mean to amass a personal army of white-knights. Altho' I admit (and it's quite obvious) that I did infact post this just to get validation from my friends. And that sort of manipulative behaviour is no better than what I dealt with. That is why I'm doubting my integrity as a person.