I'm so sorry, friend. You are definitely not a huge waste of space. We all have hard times, I am in a really rough spot as well, but know you are not alone.
The best thing to do for cyber-bully type things is to not respond. If you do, they will think they are getting in your head. I just let those kinds of people alone. But I know 100% know where you are coming from. Some people are just mean like that for no reason. It's really hard, especially if it is another friend.
As for the speeding ticket and other things, sometimes it seems like life is out to get us. I'm pretty sure it isn't, and when things like that happen to me, I try and just "escape" from the drama and bad moments of life. Usually I do something that I enjoy, like watching some Netflix and playing the ukulele by my window, or listening to my favorite band. Sometimes if I need to just calm myself down and get away for an hour or two I just do those kinda of things, and it makes me feel a lot better. But know that, it will get better.
Maybe go to your roommate and hang with her, (she seems super sweet ) and just be with each other, and comfort each other. A lot of times when the rest of the world is being sucky, I just talk about it to my best friend, and it's so great to be around someone who supports you and loves you.
Those are just some things to do when I feel horrible, and I hope it helps. I also hope you feel better *sends a thousand virtual hugs* -Jay