To answer your question, yes, it is normal in the short run. But in the long run, INTPs do not need others input and can go it alone. But finding a mate can make the journey a lot more fun.
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I have a similar problem with my 16 y.o. son, except he thinks he is not ready yet. What I suggested (to him) is to at least talk to the opposite sex. Personal experience has it that both overly controlling parents and girlfriends too soon are large problems for proper life course. So charge ahead on a charted path along the rocky shores. INTPs should try earlier than comfort dictates, for reasons of getting dragged into an individual world, IMO. <p>
So do it, find a girl friend, if your reasons are to touch into that other alternate reality: the opposite sex. Then surprise your parents with the 'fait accompli'. You might seriously consider making an active decision to taking your time on the deeper issues opposite sex issues, though, in part because that would earn respect with your parents. It would much lessen the long term trouble. It is not easy to do, as we are talking about biology and playing with flamable substances. You have years and years to go, so what is the hurry? Here is my suggestion, first quote number one, then much later adopt the below quote number two.
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Henry James -- "A man who pretends to understand women is bad manners. For him to really to understand them is bad morals."
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G.K. Chesterton -- "Men and women in the long run are too different to be successfully matched and bond as an alloy, unless in a hot, torrid, fiery furnace.
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Good Luck to you, fellow INTP. Good luck and journey in all. We can tolerate solitude much better in the long run, yet it is best to know both worlds of self and others.