How can I make more friends?

Ok so if there was a list of students who go to the school and how much they are liked, I would probably be somewhere at the bottom. It wasn't always this way, because me and my best friend who is a guy were hanging out a lot during a period of time and some girl who was jealous of me spread a rumor we were dating and then another one that I made up that rumor to get attention and he believed it and...it's really a long story, but long story short, he didn't want to be friends anymore. He just found out the rumor wasn't true last Thursday so we became friends again, but during the time the rumor was being spread, all the people I thought were my friends left because they thought I would spread rumors about them. At the moment, it's pretty much just me and my guy friend, and he's kind of afraid to hang out with me and I don't really blame him because believe me when I say the last few months with the rumor were extremely harsh, and he's like super popular and all his other friends were making fun of me. Besides him, I really don't have any friends. On group projects in school I work alone, Because my guy friend always work with the other popular kids, and i'm not trying to say he's a mean guy, because he's not, he's super nice but just a little cautious so we don't have a repeat of the rumor. I practically live on the computer in my free time because no one asks me to do anything and when I ask them, they always say they can't because their hanging out with someone else. On facebook, my sister is the only one I even talk to and she only comments on my statuses because If i try to talk to my guy friend, all the people he's friends with pick on me. Every other weekend i act and model all day, so I loose some time to ask other people to come hang out. I have really become antisocial and practically afraid of people, for example my moms sent me to a physicatrist and he said I need to start chatting on facebook as my challenge for the week, but they all start yelling at me or making fun of me. I'm so tired of only having like one friend. I think I'm a nice person, but after the rumors, no one likes me anymore. What can I do to get more friends?