Why am I so unhappy these days?

I'm a 22 year old college grad working as a designer for a construction firm that I've been with for two years. Recently my boyfriend and I moved in with his Dad and younger brother to try to save money on rent and also help his dad cope with his recent separation and divorce in the works. I also have an 11 year old German Shepherd, Angel, who is the shining light in my life, she's been with me forever and I love her so much. She recently was diagnosed with DM and can no longer use her back legs. We get around it, she has a harness so I can help her walk and she has a wheelchair to let her run and play. Anway, my life doesn't sound so bad right? Pretty decent even? Well why am I so miserable? I mean there's a little more to it, but I don't understand why I am so devastatingly sad all the time and just plain unhappy. I do hate living in this new house, my bf's Dad is a drunk, he's loud and obnoxious and yells alot, about everything, he's always asking where we're going and what we're doing and he never listens, not cool. And his younger brother (17) is just awful. He's says everything is "gay" and calls everybody a "fag", drives around in a piece of crap redneck truck and he's just also very obnoxious. He's always coming to our room trying to get my bf's attention or to tell him the most ridiculous stories, things like who he found out his ex gf just had with, things I could absolutely care less about and just want him to go away. And it feels like he's always there, never leaves us or me alone. I can't shower without him loitering outside the door close by or take my crippled dog out to pee without having to shove past him in the hallway. He's also very rude, I made some homemade cookies for everyone, two giant plates full, he ate every last one when he came home late that night, I hate him. Him and his dad just make me feel very bad when I'm around them. And at work I'm getting very frustrated. I'm constantly covering for our front desk receptionist even though I am in no way a freakin secretary. It's really demeaning being the one that has to take over for her whenever her kid is sick or she has an appt for her car, or what ever it may be this time. I've complained about it probably 10 times and no one cares. And with this economy I'm told that I should just be grateful to have a job. All these things have made me an angry person. The smallest things send me into an absolute rage. I'm miserable to be around, people don't often approach me unless they have to. Which, in a way is what I want, to be left the hell alone. But say a piece of tape got stuck to me, try to get it off a couple of times, can't quite get it, that would drive me to be so freakin angry I'd want to just smash the whole tape dispenser. I beat the crap out of my steering wheel in my car a lot, my car is like the only place I feel I can let everything out, cry and punch things. It makes me feel like such a freak, like everyone hates me, including myself. And I honestly don't really want to be liked. I don't like people anymore. I have never once met a girl my age that I could be good friends with. Most 22 year old girls that I've met (my bf has tried to have us go out with couples that he knows) are absolute skanks. And they're boyfriends are total deuschbags that treat them like skanks and they seem to like it. I feel like the only attractive girl in the world that gives a crap about being respected, I'll punch someone in the face for looking me up and down and making a comment, particularly when I'm just out in everyday life not asking for this attention at all. Other girls would be like, oh my god, u think im hot? Purrrr.thanks, want my number? What a bunch of s. And that's what guys my age expect, I hate them all. Sometimes I wish I could turn off my brain and just be like that, but it's not fun for me, I don't know why people think being skanks and ******* is cool. I mean you can't even turn on the freakin Today Show without them being like, today is Hugh Heffner's birthday, happy bday Hugh! Am I the only person in the world that's like, are they seriously celebrating someone who has made millions creating disgusting mags? Why is that ok!!! The whole world has gone crazy. I feel like the weight of it all is on my shoulders, it's never going to get better, what's the point of anything? I'll never be able to be successfull without my looks being a factor. Even in my every day job I get, wow you're too pretty to be in the construction industry, you really work for so and so? My emotions just get trampled on like an hourly basis. Some days I feel powerful and confident in myself and that I can overcome anything. But I don't know. Positive thinking only gets you so far, I just don't see any evidence of other people like me winning in this world. What am I supposed to do? Tell myself not to care? Lie to myself and say it will get better some day? Be friends with phonies because they're the only ones out there? Did I mention th