Re: Girls! So there is this guy....
the problem is that there seems to be a double standard- i.e. you feel it's ok for you to have a close relationship (even if it's platonic) with a girl, but if your sister did the same with a guy, you would not approve. I think you should live by the same standard as your sister. I would be really angry if my bro was being overprotective with me, while he was time passing- which nauzubillah I hope never happens, and I would just say "who are you to be telling me that".
Your friend I think wanted to know if you thought of her as a pastime or if you liked her. And if someone makes them selves accessible by always calling or hanging out, and you take advantage of that, then it's just as bad, because you are leading them on. Just because someone lets you treat them badly doesn't mean you should.
The way I see it, if you really want to ignore a guy/girl that is after you, it can be done- all you have to do is show no reaction to anything they're doing and be really annoyed. Most people's hearts are just not 100% into it, they like to complain about how someone won't leave them alone, but at the same time, they like the fact that someone wants them.