Fi is self-focussed in the sense of having more well-defined values that apply to the self as a moral compass. Ti is the same, except replace values with principles.
Fi and Fe actually affect both the self and others. It is not the conclusion or end-result that distinguishes one from the other, but the process in how the conclusion is reached. For example, when Fi is outwardly focussed, it is usually due to a personal moral value of helping others. Fe on the other hand, will help others because others want or need the help (regardless of whether or not others actually ask for the help) and Fe wants to fulfill that need. Fi can be selfish in the sense of defining the self from within. Fe can be selfish in defining the self from without. For example, an Fi person might go out and buy a nice sportscar, because he/she really likes fast sports cars. The Fe person may also really like fast sports cars, but a lot of weight in choosing a specific sports car, may come from how he/she thinks others might like his/her choice.
Ti and Te can also reach the same conclusions, but will use different processes. Ti person may want to help others because it is an internal guiding principle. Te may also have a guiding principle to want to help others, but is often out of convenience and if the required work is somewhat minimal. IE if I do this work for my boss right away, he will leave me alone for the rest of the week.
An INFP friend I have values optimism and tries to be positive to feel good. An INTJ friend I have uses optimism as a logical principle. She sees the logical sense and benefit of being positive, so strives to be positive.
I also posit that Fi and Ti is the process used for defining one's self. INFJs may often feel less well defined from within because Ti is a lesser shadow process. They seem to know themselves better amongst others and feel lost when by themselves. It does not mean that an INTP or INFP never feel lost or that they are fully defined, it's just that they have taken more time to define their values and principles than others.