Psychologist Allison Conner wrote an article about the top ten mistakes people make while dating. To summarize,
1. Game playing: to protect your ego
2. Talking too much about your ex: This information shouldn't be shared too in depth at the beginning of your relationship
3. Fantasizing about the future (mostly women): For example, trying the guy's last name with your first name after the third date.
4. obsessing over details: worrying what others think, your parents, etc.
5. ignoring red flags: If he kicks your dog, has anger problems, etc.
6. Interrogating your date: asking how many kids they want, or when they are thinking about marriage, that's scary for young people
7. Avoiding Intimacy: Self Explanatory
8. Rush in, Rush out: Getting overly involved, then dumping someone after a short period of time
9. Not being honest about your needs: you can't pretend everything is ok forever
10. Sacrificing too much to get the relationship: you shouldn't have to lose your friends and family to date the man/woman of your dreams
The official article is here: http://www.psychologytoday.com/blog/therapy-in-mind/200910/top-10-dating-mistakes
A video related to the article (the mistakes are a little bit different): http://www.youtube.com/watch?v=g19gB7vm2Jc
Other facts from http://www.lovepanky.com/love-couch/sweet-love/strange-facts-about-love.
Love does indeed physically make people crazy. It causes Serotonin levels in the brain to drop which can lead people to obsess over their lover. Also, it ramps up production of Cortisol which leads to higher blood pressure and possible loss of sleep. Also, scientists have found that when people look at a new lover, the neural circuits in charge of social judgement are suppressed.
Also, a break up can be just as hurtful as a real physical injury. Finally, Scientists are beginning to believe that blushing and having rosy cheeks actually make them more attractive to men, because it signifies good health.