Ex possibly ruined my desire for another relationship

As a forewarning, I tend to elaborate far more than I need to, but I will try my best to keep it simpler. Okay... so about 3 years ago my ex broke up with me. While we were together, I was feeling pretty good about our relationship, even though she did treat me like crap pretty often (her nickname for me was "man-servant" if that gives you any indication). It was my first relationship, though, so I put up with a lot of it simply because I didn't want to fuck things up (read: I had no spine at the time). For those not interested in the back-story, skip down towards the bottom and look for a row of asterisks. For those interested, the break-up was... awkward. We were renting a two-bedroom apartment at the time, but she had gone home (about 60 miles away) at the beginning of the month for summer break after finishing spring quarter at college. I was working a shitty part-time job at the time and didn't have any vacation hours to use, so I ended up staying at the apartment by myself. When she came back at the end of the month, she seemed really nervous to see me, constantly avoiding eye contact and showing no signs of affections. Of course, being the lovestruck fool I was, I was just happy to see her and didn't really notice. She asked me if I had seen the movie Nine and when I said no she suggested we go watch it. The walk to the theater was quiet, but still I didn't notice anything. After the movie we went back to the apartment. We chatted about the movie for a while, then I went into the bedroom to take my shoes off, put my belongings away; the usual routine for when I get home. She then said she wanted to talk about something in a lower-tone: I knew something was up then, but still had no idea what was coming. After I sat down she looked at me for a second, then looked away while saying, "I don't think... we should date anymore." Now, those of you who have been through a breakup know how hearing this feels: like your heart has been torn out and a fuckton of bricks fell from an airplane, smashed your heart and then got crushed by the plane. Then King Kong comes over and takes a massive shit on the wreckage and jerks off on top. I tried asking her why, but of course she couldn't tell me. She was crying heavily and could tell I was distraught. Not sure how to feel, I simply left the apartment and went to work. My coworkers were surprised that I was back, so I told them what happened. Several hours later, upon returning to the apartment, I discovered she had left. There were no notes or anything for me, so I assumed she had just buggered off to leave me be. For whatever reason, my first instinct was to rearrange the furniture in the front room. Maybe I just needed to change something, I don't honestly know. Then I started putting all the notes she had written me (I kept them all) on the bed for her to see. After that I hid the cable to her laptop and changed the password on the wireless router, then went into the second bedroom, locked the door (it had a chain-lock) and tried to fall asleep. Needless to say I was awake all night and heard her come back sometime early in the morning. I was expecting her to be confused as to why the front room had been rearranged, and a little angry that she couldn't charge her laptop or access the internet. What happened was much worse. She began yelling loudly, throwing things at me and saying that she would call the cops and say that I had not only stolen from her, but that I was abusing her even though I had never laid a hand on her (although she hit me constantly, claiming she was "love punching" me). She also threatened to have me evicted and removed from the rental agreement. I had seen her angry before, but never this angry. To make things worse, her dad was a cop, so she had some potential leverage in that area. So I gave her her shit back and went back into the second bedroom. I didn't sleep for four days. Every time I left the room, she would mute or pause what she was doing and would simply watch me with this evil look on her face. The following week my family came and helped me move out. ************************ If you didn't read the backstory, here's where it ended. But basically, because my ex treated me like shit during the relationship and during the breakup, I've found it incredibly difficult to trust women. Sure I've developed crushes on a few since then, but I don't know if I'd ever actually be interested in being with someone again. There are things I miss about being in a relationship, but overall it just feels like a massive waste of time, money and emotions. I haven't socialized with anyone for months, actually, because I just haven't felt the need to. Has anyone else experienced this? And if so, how did you overcome it? I'd prefer not to be alone for the rest of my life, but I'm having a hard time convincing myself that being alone isn't a good thing.