http://www.womenagainstabuse.org/index.php/learn-about-abuse/teens
http://m.loveisrespect.org/dating-basics/what-is-dating/what-should-I-look-for
Teaching pre-teens about dating and domestic violence is so important for girls AND young boys. Too many times we allow hormones to take the place of parenting. Children should START dating armed with this knowledge. They are too precious and the stakes are too high to allow them to learn by trial and error. If we send our kids out into the world of puberty without discussing what love can be and what it can't then we are sending babes into the lion's den. Please share this with your child before they even show interest in the opposite sex. That way it won't be taken as a personal insult to your child or the person they chose. Teach them that there is nothing about hitting, lying, cheating or controlling that is love. Even if a person professes a change still do not allow someone the opportunity to practice again on you. If one truly has changed then they can find another person to try again. No one hits you or cheats on you twice. Teach this mantra and ask your kids to say it until they mean it.
More resources
http://www.cdc.gov/mmwr/pdf/ss/ss60e0606.pdf
http://startstrong.futureswithoutviolence.org/why-middle-school-matters/