Depressed about being alone?

[Fort Lauderdale guy]

I just turned 18, but feel depressed all the time about girls. I am a pretty introvert guy at first which gets hard at times and it just brings me down. I feel out of place often and just get stressed out. I try to open up and act extrovert but just feel out of place. I work and breathe with all extroverts and am bad with meeting other girls. I work at a college cafeteria on the weekends (still in high school, senior) and like this one girl at another high school shes going there next year but I have never met her before I see her all over social media but I went to school with her sister but barely knew her either. I don't know why I feel so attracted to her and she seems fairly extrovert and a big into partying. I want to talk to her but i would feel socially awkward and online would feel like a creep. I am going to a different college but we will be in the same town so it's just hard cause I like my job but know I will have to quit because it will kill me every time I see her. I try to forget and move on and focus on my own life but sometimes it just gets hard. Just looking for some suggestions. Thank you.