How come in free fall you feel weightless even though gravity is pulling down on you? (ignore air resistance when answering this question).
The reason you feel weightless is because there is no force pushing against you, since you are not in contact with anything. Gravity is pulling equally on all the particles in your body. This creates a sensation where no forces are acting on you and you feel weightless. It would be the same sensation as if you were floating in space.
Because you never feel your own weight! I'm sitting on this chair to write this, and I can feel the push of the chair up against my body. That is what I think of as my weight - but it is not - it is the push of the chair against my body in response to my weight! If the chair disappeared I'd be in free fall, and I still wouldn't be able to feel my weight, and I wouldn't be able to feel the push of the chair either - I wouldn't feel any forces at all. This is what people really mean when they say they feel weightless - they mean that they feel no forces on them. (Your weight of course, even though you can't feel it, is there all the time, whether you're falling or not.)
You don't feel gravity pulling on you, because gravity doesn't actually pull on you or anything else. Gravity bends spacetime. What this means is that your own perceived frame of reference (a system of coordinates to measure space and time), which is all nice and straight, does not match up with the actual shape of spacetime. So even though you think you are accelerating, you're really not. You're just following a straight path in spacetime at a constant speed. When you translate this motion into your own straight frame of reference, it appears as if you are moving along a curved path and/or as if you are changing speed. This is why there is a mismatch between the sensation of freefalling and the apparant motion of our body while doing it.