What can i do... when i feel completely down and no one to talk to? feel like dissapearing.?

last year something happened to me and i think that i really was in like depression, i ignored mi friends on purpose and stopped talking in class. then summer came, i had to go back to where i was born for the whole summer, but since my friends werent there, and i told them that my email wasnt working, i didnt really talk to anyone much and my thoughts got worse. . . . then school started in sep then i tried to be undepressing looking but then a few months later i figured out that i smiled way too much. and last month, i read an essay that mi friend wrote with me in it from sep, and it was scary , she had always been asking me the whole year if i was okay and i always said yes. and now, im not as shy anymore, but i dont want to seem to want everything but just that there are so many times when i feel like i want to dissappear,i really dont like myself much at all right now, i was always happy when i returned during summer to the country i was born, but this year im beginning to think that i dont feel like im even from that country much, like i dont belong there. then suddenly summer has been starting to get depressing again, and im just scared it might get worse, because i really dont want to talk to my friends because i;ll know that ill worry them . advice? ty