Funny, part of that sounds like myself. Im also very picky about who I let in, and once your in I care deeply. Its actually a bit the other way around with my enfj friend, first when we met I had a quick negative opinion of her (later it turned out that I was totally wrong) and she kept coming back to me until I let her in, Im so glad I did! It makes sense though, this roles being reversed thing, I mean we only have the I and the E as differences.