I agree with so much of what each and every previous poster said here. And this makes me kind of
As for myself, it actually depends on the people who have been granted the chance to get close to me. I test people too. And too much for my own good.
Just as aphrodite-gone-awry said about the 3 strikes, it is all about strike 3 and you're out for me as well. You're out for this time. Sure, I might still let you try again but it's going to be twice as hard the next time.
And this could be called a "problem". Maybe it is about having too high standards. I expect a lot from people (and it actually isn't something unrealistic that cannot be reached by everybody), and I expect even more from myself. And I know that once I'm in, I'm in for good. But if others fail to show that they're prepared to be in it for good as well, things just wither away. Something is just broken after that.
I agree with what the OP wondered about the INFJ's:
It's a vicious cycle