Life makes you crazy. I think a challenge for Fi users - particularly XNFPs - is learning to trust your gut and learning how and when your gut is accurate (and when it's not). I guess it's not necessarily that it's Fi that is accurate or not, but that "gut feeling" I think it's harder for INFPs than for ENFPs to articulate to others what their Fi is telling them.
Developing and trusting intuition takes time, more for some than for others.
Everyone has to learn to stick to their guns when they know something is 'right' whether or not they are ultimately correct. Part of it is a leap of faith. Part of it is predetermined by how we're wired. Part of it is asserting your ego on the world and your right to exist.
Damn...am I making any sense today? Bah.
But yeah, once you hone it and work out the kinks and basically once you trust your intuition, stick to your guns.
Of course, you will probably annoy the shit out of non Fi users, and some other Fi users who don't understand your reasoning. LOLOL.