Search Results: being too mature in a relationship

If you met a girl who you were really attracted to but as you guys started hanging or hooking up more you realize she is really guarded emotionally, I see you as having a few options (or rather these are things I've seen or experienced):

1) End it there
2) Be clear about your intentions, see if she is on the same page and if so cool, if not then end it
3) Continue to pursue her without telling her anything, then leave whenever
4) Tell her you really like her, pursue her into more than sex to exclusivity, then relationship (she's clearly letting guard down) and leave her immediately and out of the blue

Sorry I know this is a weird question haha but the 4th just happened to me (I'm the girl) and it messed me up especially as I tried to keep it sexual without feelings in the beginning but he pushed for more and its happened before on a smaller scale with a guy who was my friend before hand (both acknowledged me being guarded).
I just can't imagine why a guy (though girls do it too) would openly acknowledge a broken person, see it as a challenge and push them to open up, when they never had any intention of sticking around. I just want to know how you guys would treat this situation and if this is normal or if I have bad luck or even if people don't realize the damage they are causing.

PS I know the mature thing to do is option 2 but seeing as none of us always choose the "right" option I want to know what you guys or girls have done in the past or think you would do --- no judgment, simply curious as I've only been on the receiving end