I feel lonely 😞

Hey guys, I’m 17 and I haven’t dated since freshmen year because he took a lot of energy out of me plus we were together for a year. Anyway, I’m feeling lonely but I can’t seem to allow myself to open up to a new guy because I keep thinking to myself that I’m wasting my time if I do. I know it’s wrong and not exactly the best thing to do but the thought will shut my brain down. I just don’t want to be alone anymore :(