I can't answer your question, but usually dashlights and taillights are on the same fuse [circuit], and NOT with the head lights. Answer 1 is correct as, normally, the headlights are on a "dedicated" circuit, with NO other lights or devices sharing. I suspect this is a designed in safety feature due to the potentially critical function of the headlights. Therefore, the fact that the "dash lights" continue to "work" is immaterial to the problem with the headlight. Now, to the more important OTHER part of your question. NOTE that ANY TIME you have a FUSE WHICH CONTINUALLY "BLOWS" upon replacement, INDICATES SOMETHING IS VERY WRONG !!! A fuse is SUPPOSED to blow out anytime there is an OVERLOAD or a SHORT within the circuit which it PROTECTS. See a related question and answer, "What are the origins of the fuse?" This related question and answer contains a comprehensive discussion of what your repeatedly blowing fuse means. The bottom line of your problem is that there is definitely something SERIOUSLY wrong with your headlight circuit, and if not properly analyzed and corrected, could resuslt in a serious nighttime accident, OR serious damage to your vehicle's wiring system, or worst case, a fire. Please read the referenced question and answer, and if you are not capable of finding and correcting the fault in the headlight wiring circuit, then get a PROFESSIONAL AUTOMOTIVE ELECTRICAL TECHNICIAN to fix the problem before it results in serious consequences.