I feel really unhappy, help?

Recently I've just been feeling really depressed, I'm not sure if it has anything to do with my hormones (im 14). Sometimes for no reason, but when I think beneath it i can see why. I have a good family and friends, but sometimes my family really annoy me, I sometimes feel they don't really know who I am. I have some good friends too (I'd rather have a few close friends than a load i dont really trust). But sometimes they can irk me, like, if one of them says something and i could take it as an insult, next minute im really sad about it. its like one tiny thing can change my mood so quickly. the weather also gets me down in winter too. I dont really like the way I look, although recently I have lost some weight so I'm feeling rather happier. I also feel I don't really have any talents AT ALL. People say im good at art, but when I look at everyone elses I become instantly jealous. My grades are usually average. Some days on the weekend I feel extremely bored too, like there is nothing to do.. (more in winter, though) and recently i just feel not being alive, like theres no point..