Throughout my life, I noticed that I have the ability to make people trust me with their innermost secrets, even after a week of meeting them. This has helped me with my self-growth, hearing from people the experiences they have gone through and understanding where they are coming from. Just be wary that with the power of Fi, there comes some responsibilities. I noticed that guy friends who have bared their soul with me and trusted me with their problems, and such, tend to like me romantically after wards.
Fi, being my base function, has helped me tremendously in many ways. It makes me fully aware of my feelings about myself, and how other people are feeling as well, and often why they feel that way. I can pinpoint exactly what is bothering 99% of the time having this high self-awareness. With this in mind, I then avoid the people who make me feel "uneasy."
The ability to give genuine compliments, see the good in others also is Fi. At work, I have encountered people who initially did not like me, after noticing what they do best and giving them genuine compliments (or gifts) at appropriate times, they end up liking me. There is always something good in each person. When this is brought out in the open and recognized, their heart soften and feelings change for the better.
For me, Fi is the ability to gain trust, ability to appreciate others, and the ability to understand the feelings of oneself and the feelings of others.
How has Fi helped you in ways?