I'm a 5'6'', 175lbs female who can do deadhangs. Got there through Olympic lifting and adding on barbell rows, body rows, and negatives.
Being lighter makes pull-ups easier, but being heavy doesn't mean it's impossible--you just gotta be strong enough to compensate.
I should also add that I know where you're coming from--I've been losing weight on-and-off for a while and was sure I would never be able to do pull-ups until I lost a lot of weight, and wasn't even sure then as a healthy weight for me given my body fat percentage is probably 150-155. When I got them it was a pleasant surprise!