Can someone tell me where all the common sense has gone?

I am really at a lost as to why some many stupid young girls are have children by young man who sticks around for but disappear when you say I am pregnant.... And he winds up in another girls arms..... While you are suffering having his child... Then he looks into your eyes and says its not mine... And who else have you been sleeping with..... And all you can do is cry your eyes out because of his betrayal.... When are you young ladies going to wake up and learn how to say no or if you must have then you should use the proper equipment that will prevent you from getting pregnant......... And if the guy say no than you say no.......... When are you young ladies going to wake up and understand that any man will tell you anything thing that will enable them to sleep with you........ And please will some young lady between 12-17 tell me what they know about raising a child and teaching that child certain values so that when they are between 12-17 that they won't have the same problem that you had at 12 to 17.... And will some young lady tell me what kind of Job will you get at the age of 12-17 that will help you support yourself and a new born child..... Please help me to understand why you would do thing to yourself when you can just say no or use the proper equipment that will protect the both of you from having a child before either one of you have a job that will at least help you to buy the things that a new born child need..... And why curse me out or call me stupid names when when you are only 14 and pregnant................................…