Warnings :

In the case of trying to get a date, if the person who rejected you starts making "advances" on you after he or she has rejected you, but he or she still does not want to see eye to eye with you by being partners or getting more deeply involved, you have to ask yourself if you enjoy simply the flirting pleasures. Many people will not get any pleasure out of it because they know it will not lead anywhere. If you find yourself to be one of these people, then express your disinterest to the person. If things get out of hand and he or she refuses to become intimate with you, but keeps on flirting with you, and you still find no pleasure in the flirting, you may want to break off contact with that person because you find no pleasure in being with him or her. This does not mean you wish bad for the person; it's about self-protection and keeping things real.
People won't always get back to you when you ask for feedback on rejection. That's life––sometimes they're too busy, other times they're at a loss for words as to how to explain something in a way that won't sound too critical or personal. And sometimes, they truly can't be bothered. Again, don't take it personally––see if you can find someone else you trust and who does have time to go over what happened with you, to try and see how to make future improvements.
If you keep taking rejection extremely personally, consider speaking to a counselor or therapist––if you are suffering from depression, anxiety or other mental health issues, you might not have the resilience needed to cope with life's ongoing pressures and need added support. It's nothing to be ashamed or afraid of––every person needs a compassionate guide in life now and then.