Miserable

Lately, I haven't had the best attitude. I find myself getting extremely angry at small inconveniences, and eight hour shifts at work that once flew by now make me want to hang myself just to make it end. The customers are grouchier, my fellow associates are grumpier, and I'm mentally disemboweling people several times a day.
I wouldn't say I have a thick skin (quite the opposite), but yesterday I cried the entire drive home from work and that's not normal. What got me so worked up? Nothing in particular, just bad customers and an even worse manager. It wasn't anyone's fault, it wasn't even the manager in question's fault. I actually like her, outside of work. But at work I sometimes daydream about slapping her. (Don't worry, I wouldn't ever act on it). I'm not sure what caused it all to bubble to the surface and escape out my eyes. I was just miserable. I still am.
Maybe it's all the holiday bustle, although that's unlikely because usually that puts me in a good mood, or maybe it's because work (which wasn't very fulfilling anyway) has now become endlessly tedious. It's not okay to expect someone to be able to smile and be cheerful for eight hours straight. Especially when most of the customers she must be cheerful and overly helpful to are rude, insulting and just plain cold. Without being able to distract oneself and give oneself some small feeling of accomplishment, it all becomes undeniably pointless.
I realize that this is a long and rather depressing rant, but I can't help it. Well I guess I could help it, I don't have to write any of it down, but I'm not going to help it. I just have to look at this as a positive. There are still things I like about work. I like a lot of the associates (many of whom bring homemade baking!), I'm allowed to wear jeans to work, it's relatively easy (except for the strain on my sanity with some difficult customers), and it's helping to pay my bills and feed my loved ones. That's not bad. Aside from the bad days here and there, overall it doesn't usually get me so down. This is just a momentary lapse. It'll get better, and until then I can always rant.