Holding things in can make you POP!

I need to vent. This will be a long blog for I fear that I have bottled so much in. For those of you that did not know, I run the order desk for a cabinet division. I used to adore my job. The last 5 months have gradually become a syrupy hell.
At first I tried to let things go… but now everything is building up and I feel like I am going to lose it. It takes all my power to fasten it tight within me.
I will try to clarify things the best as I can, as nobody works here and knows the routes that we need to take as the order desk.
My company has been getting massive projects in, and we have opened a new store in Denver that I am in charge of entering into the computer and organizing. I am in charge of discounts, delivery, points they earn for the orders, and receiving payments.
In my division, my boss and design team are not familiar with the ordering procedure and are not used to big projects. As you can imagine, it has been frantic for that very reason. I will enter 10+ orders that take quite a bit of time. After I finish them, my boss will come and tell me that we need to apply a 15% discount when prior to ordering the orders I was told by my sales manager that they needed a 20% discount. So I will go and fix all of the orders. After I fix the pricing that my boss told me to price it at, my sales manager will call me and tell me to change it back to the 20% discount. This will go on most of the day. So after fixing several orders and projects over and over AND then trying to enter all of the other orders that come in… my mind is just pottage at the end of the day, and by the end of the week I am washed-out.
Policies. The order desk gets drilled into them that we need to stick to policies no matter what! We need to be the bad guys and stick to our guns. Of course when we do, in most occasions, we do not make the customer happy. The customer will go to their sales rep., the sales rep goes to our boss, and then our boss comes to us and over rides the policies that we were supposed to lay down.
While this idiocy is going on, there is a fellow employee of mine that is very dependant on me. This person cannot do anything without asking me HOW to do it when I have demonstrated it at least once everyday for the last several months. I feel bad but I lose patience as this should have been known by now but this person won’t take the time to learn and expects me to hold her hand and do everything for her. I have tried to not help and tell her to figure it out (I word it nicer) and she will wait until I do help her. When my boss comes around she will turn it around and try to make it appear like it is me that is being intricate so she looks good when she has no clue what to do. This person will not enter any orders unless my boss is around also. When she does do orders she forgets a lot of the product, or even enters the WRONG product so I am continuously fixing things for her. This person will talk on messenger to her friends all day and color in a coloring book. This person is very strident and very flirty with every gentleman that comes through the door. This employee has no tact; she made my good friend at work cry last week. I could go on for days but this is not helping the work atmosphere. OKay okay.. I will be fair... some days this person does amazing and I am proud. But those days are rare.
Everyday I do abundant amounts of credits, returns, and warranties. Before you do any credit, return or warranty you need to research it and make sure that it is applicable. At least once a week I will do my full research and then process my warranty, credit or return. Without fail, the next day I will have my warehouse manager and boss gain up on me and tell me I was incorrect. I will bring forth my research and why I processed what I did and they will still say I am wrong and then later I find out that they have had problems with certain customers and they did not want them to return some items or issue them credits. Why can’t they just tell me that to begin with instead of demeaning me? To top it off my boss will send out an e-mail saying that we need to research our credits, warranties, and returns. HELLO! We do what they ask us to do and then they reprimand us.
I could go on forever. But all in my entire work environment is uncomfortable, unorganized, and people here are unappreciated and we get yelled at all day by bosses or customers. Not to mention some of the relationships between some of the employees and my boss are unappropriate. It was not always like this. I find it funny that my supervisor (who is amazing!) tells me all the time not to quit and that they need me. I have never said I was going to quit, but she see’s what I go through and she tries to keep me here (bless her heart). Some days are better then others… but I feel that I am at wits end. I gave you a brief explanation of half of the things that occur here during the week. I don’t know what to do to better anything. I have tried to talk to my boss about a few things and he blew me off. I don’t know what to do anymore.