Jealousy Problem??????

I get jealous of people quite easily. I'm a 13 year old girl. If I see a girl with a cute hairstyle, I get jealous, or a very pretty girl, I get jealous. I am also jealous of my neighbors. They have so much stuff (pool, hot tub, trampoline, etc) They are always out swimming with a bunch of their friends or I can hear them having a good time on the trampoline. When I have no one to socialize with in my backyard or anywheres, I get very jealous of anyone who is having a good time. My other neighbors let me use there pool next door any time though. That's a good thing, though. I also have another problem. I only tend to hang out with the same 3 people all the time. Whenever they aren't around, I'm always sitting around doing nothing. Please help me with that too. I think if I just call someone else up randomly they'll think it's weired. Is it true? It would be great to help me with both my jealousy and friend problem in one answer. Thank you.