i have my own answer, to this question that is just asked all to much, and usually if someone seriously asks me this i just stop talking to them. but, in all seriousness i thought it would be fun to hear how the rest of you have answered this question.
for me, i never earned as much working as i did through investment activity, and so i got this question a lot from mom, girlfriends, and well generally people i just do not talk to any more.
In general, you will need to find like-minded individuals who have started their own businesses, regardless of field or age.
At the same time, you do want to meet people like you (in person) even for short bursts of time. Not just older adults who have had their own business, but young people your age also cutting their own path.
In a few years, you will find that many naysayers will have lost their jobs, swapped careers, or switched majors during the several years they've been telling you to get a job. Only then will they realize that you're not doing this to avoid work, but to ensure work. Employees who don't like their jobs will feel you should suffer, too. Employees who are happy with what they're doing won't tell you to get a job in a negative tone. Instead, they'll be impressed and tell you to keep at it.