Great link to enlighten those who lump Fe and Fi into a blob. Here are the most relevant parts (in my most humble opinion) for the lazy people:
"Here's the thing: one hallmark of introverted Feeling is to withdraw, to end relationships. This process is the one most likely to treat another as persona non grata when a value has been violated. So look back over your life now and notice all the times you've walked away, turned your back on someone, ended a relationship. Those would be manifestations of introverted Feeling.
And we've all done it. Every one of us (I believe) has felt obliged to end a relationship for one reason or other that probably had to do with our values. By extension, we may rely on those examples as proof that ALL of us can and do use ALL of the processes. Nobody got overlooked when it came to the introverted Feeling function.
The piece to notice is how readily doing that comes to you, and how easily or gracefully you do it. Chances are that people with introverted Feeling as a preferred process do it with greater style and grace than those of us who (like me) prefer extraverted Feeling.
I don't agree, however with the "easily or gracefully" bit for Fi versus Fe. Dude, it hurts a lot! I suspect that it's not easy/easier, but necessary for certain people. BTW, it's notable that many INFJs (Fe) seem to find cutting out necessary as well. In summation, rationals, we feelers are with you!