How to get over your first love?

My boyfriend of almost a year and I broke up back in August. Since he was my first almost everything it’s very hard for me to get over him. It’s been 2 months and I still think about him every single day and I keep on stalking him in Facebook even though we aren’t friends. Well a few weeks back I found out from a friend that he had “poked” one girl on Facebook and so I got really jealous and blocked and deleted him.

I became jealous and also kind of annoyed because it had been only a couple of weeks since we broke up and I feel he was already looking into talking to other girls which did not make me feel better. Now I’ve just been spending all my energy looking through his Facebook page and it seems he’s enjoying himself while I’m here all alone and miserable.

Also I had this really good friend of mine that I’ve known for about 4 years or more. Her and I were together in school and lived in the same neighbourhood and then one day we had an argument over a stupid little thing and she got really mad and blocked me from her life, we haven’t talked for almost 4 months but her and my ex are still friends on Facebook and today I noticed she’s been liking his recent activities and commenting and all that which made me explode. I just couldn’t stay strong anymore and it really hurt me. I counted on her as one of my best friends and since she’s been sleeping around a lot I’m now worried that she’s going to move on to my ex.

Help me, what should I do?