A lot of women struggle to do a single pull-up. But this simple little rethink may make things a bit easier.
When attempting to do a pull-up or chin-up most people will focus on bringing their chin to the bar. This method usually has the effect of craning necks and over demand on the biceps. Instead, focus on bringing your elbows down and towards your hips. This way you are better likely to activate and engage the large powerful lat muscles (that are primarily responsible for this move) and take stress off the arms and neck.
Pull-ups aren't easy. But keep practising and keep your head in the game by good visualizations.