I do not doubt you worked very hard to prepare and had everything lined up to pass. I don't know which knowledge areas your test found deficiences in, but I would start there. Naturally, those areas will be the ones to begin re-strengthening your grasp of the concepts taught through PMBOK.
There are a number of ideas we on the forum could share with you.
What would be helpful is if you could tell us what your study plan was, what resources you used, what mock tests you used, and how did you do on those tests.
The last piece I think to say that could bring you some encouragement is this is not a barrier. It might be a stumbling block, but nothing that is insurmountable with some re-training. If you find you still desire to test for the PMP, please create a goal (timeline) and focus on passing.
Don't give up! I'm sure you're feeling very discouraged, but failing the exam is more common than you might think. The test is honestly quite hard -- that is one of the reasons why the PMP is a respected credential. It takes actual experience plus the ability to pass a very lengthy, challenging exam. There are other certifications out there that are much more of a rubber stamp -- and consequently, they mean a lot less. Stick in there! All the work is worth it in the end.
I agree with Michael -- in order for us to be most helpful, it would be useful if you could share some information on how you prepared, and what you feel your problem areas were. That way we can tailor our advice to be most effective.
If you want general advice, there are a lot of "Lessons Learned" from others who have passed the exam, in that section of the forum.
I agree with both Michael and Steve. I do think that the quicker you return to studying the better since the information should still be fresh. Hopefully some of the Learned Lessons here on the forum will help you. You can do it, don't give it.