Please help. My mother is driving batty ?

Right so i love my mother to bits but shes driving me crazy. she has a bad grace with what ever i do from the way i lean the sink to beening on the laptop she always like cant you not be doing something else. she always has a bad grace if i ask to have anyone over and then when their over shes all nice to me and them if i say il get them food or clean up shes like no its grand il do it without a word and then when theyer gone shes like you do nothing around here. and you want us to get you a car and demand it off us when very clearly thats not true cause i really dont. it was her birthday the recently and i was the only one who thought of it not even dad or her sister thought of it but me her daughter did. i asked her would it be ok if my boyfriend came up and she just said give me a break will ya i want the house to myself when she always has it to herself. then i asked could i go down to him then and she just said no i dont have the money what the hell do you think im made of then she just sparked off a row with me over everything. she honestly made me cry cause i do try my hardest around the house and to help and she just basically tells me thats not good enough and that i shouldnt want people in the house? someone please help me why she dose this to me please?