Just remind yourself that the crush you are feeling is equivilant to cocain and that it evolved in us to make sure that we mated and pair bonded. As long as you remember that you would be doing yourself and the other person a diservice by pursuing a relationship or meaningless sex (probably) you will make the right choice. If you are experiencing withdrawl (as with cocain) and are tempted to get into contact with the person, distract yourself with less intoxicating things (in combination if you have to) candy, video games, work, study (even if your not in school). It won't be fun but you can win. Good luck.