How can i get over my trust issues?

ok so i'll be a sophmore in highschool this year and i have some intense trust issues. i dont trust anyone, im afraid of loosing the ones i love, and i feel as if i push ppl away. i've had alot of loss in my life. both my grandparents died when i was in 4th and 5th grade, and that was hard cuz my family was always at thier house, and i miss how loving they were, and they cooked for us and stuff, and showed us how to play piano and being with them was a fun part of my childhood. that affected my mom cuz they were her parents and she devolped horrible depression and lost interest in doing things with me and my brothers and sisters, then my dad devolped cancer and he died when i was n 7th grade. i miss him so much, ik he didnt want to leave but it made my mom even more emotionally unstable and she gets mad at me and my siblings alot now cuz she doesnt have our dad to help out and she doesnt know how to dicipline my little sister and stuff so she just yells and then brings her trouble out on me and my older bro's and sis's, even over little things,like the house being a bit messy. i lost a boy i thought i loved in 6th grade cuz he moved schools and never talked to me again (he was my first kiss). then i got in a huge fight with my best friend in 8th grade and she never talks to me anymore even tho we grew up together. she became more popular then me and stopped inviteing me to her parties and to her house and stuff cuz i wasnt "cool" enough. then this year my 2 best friends were talking about me behind my back cuz i saw facebook messages they left up on the computer when i was at one of thier houses about how much of a dumb blonde i am, and how im supposivly "easy". and that im annoying and they cant wait for me to move to my new school this year. so i didnt confront them about it, rather i just never answered thier calls/texts/messages i just ignored them hoping they woudl know i was not going to be bossed around anymore. then i liked this guy this year and he liked me, we texted, skyped, and he carried my books for me to class. we almost dated, but his ex-gf decided to ruin that. she had a huge bday party, and invited liek everyone includding him except me. and she told me to back off. so i tried to but i liked him too much until i met this other guy at school who seemed funny and sweet. so i turned to him and his redneck friends instead cuz i felt like it woul never work with the other guy, and i told him i couldnt hang with him cuz i would be hanging out with this other dude. so i hing with the new guy and his friends, i didnt relize how much of a jerk he was tho, he would make-out with me then tell me im too innocent cuz i ddint want to go further with him then makeing out and stuff, then i was dumb and drank vodka with him and his friends one night, and my mom smelt it on me when i got home when i was drunk even tho i tried so hard to hide it, and she doesnt trust me anymore even tho i broke up with him. i got in the wrong crowd over holiday break and went to a few parties and thought those ppl were real friends, but they only hung with me if i would drink. i would met girls that i would think were my friends but they were just party girls and wouldnt talk to me if i didnt party. i met guys at these parties who would tell me they liked me n stuff but then id find out they had girlfriends. i dont have any cofidence now cuz i practically have no friends anymore, im trying to meet new ppl, i play summer sports and do summer tutoring, but i just new make a strong connection with anyone cuz i dont want to cuz i trust noone. and im going to a new school this year, i want it to be differnt and i wat to hang with ppl who liek me for me and not cuz i will drink with them or be a slut or anytihng. how can i overcome this and open up to ppl more? am i theo nly one who feels this way??