http://www.scarleteen.com/ is a pretty decent website with sex education for young people, and Changing Bodies, Changing Lives is a good book.
These resources should help you learn to masturbate and get more comfortable with your sexuality. It's important for you to learn to orgasm. This will help you to teach your partner how to help you orgasm, which in turn will increase your enjoyment of partnered sex.
If you just do sex for your guy, without enjoying it yourself, you'll always have a low libido. You need to figure out how to make it just as good for you as it is for him. It should be a mutually fun, satisfying activity, not one-sided.
As for your excessive jealousy, therapy may be a good idea, but also self-control. You can have all sorts of emotions, but that doesn't mean it's okay to take them out on another person. A therapist, or a good self-therapy book, can help you learn something called 'distress tolerance'. That is, the ability to withstand unpleasant emotions without acting out. A really good resource for this is the book The Happiness Trap.
Hope some of these ideas help.