I can understand that such a situation might be hurtful and disappointing for a person. It's natural for anyone to feel unappreciated or taken for granted if their friends only reach out when they need something and neglect important occasions like birthdays.
If you find yourself in such a situation, it's essential to communicate your feelings with your friends. Express how their behavior makes you feel and the importance of mutual respect and appreciation in a friendship. If they truly value your friendship, they will likely understand and make an effort to change their behavior. However, it's also important to evaluate whether these friendships are healthy and beneficial for you in the long run. True friends should support and care for each other, not just when they need something, but throughout the ups and downs of life.