jgnat brings up what I think is the greater issue here. It's not about you or me, or what is right for my body, or my choice, or how many times I have the flu, or how strong my immune system is, or the legion of anecdotal tales that have been posted here.
The larger concern should be for the very young and the elderly, because our decision if it does not immediately affect us most assuredly will affect them.
Along with this is understanding how the virus mutates and changes through the course of a typical season.
What is considered to be the most lethal flu pandemic, often mislabeled the Spanish Influenza, actually originated in the midwest US and was spread to Europe by US soldiers traveling to Europe because of WWI. During the life course of this particular virus (a swine flu variety) it mutated into a much more lethal form. If immunization would have been available at the time (and used), there is little doubt that the virus would not have progressed to such a virulent strain. Millions could have lived.
This is the reason why when large percentages of the population are vaccinated, it is an aid to prevent viruses from changing into truly lethal forms. It is why the CDC keeps such close tabs on the current flu viruses. When large percentages of the population opt out, for whatever reason, it guarantees that in the future another truly deadly strain will be produced.