I don't understand these people

I'm Chinese American. There are many aspects of Chinese culture that I sort of understand because of traditions passed down to me by my parents and grandparents, such as celebrating Chinese New Year, eating with chopsticks, rice porridge to cure a cold, taking tea without any sugar or milk, and treating teachers and elders with utmost respect. Yet, now that I am in China, I find Mainlanders to be incomprehensible.

1) Why does every friendship seem to have an ulterior motive, which in my case, usually is English help? Do Chinese people ever make friends for the sake of the simple pleasure of a person's company?
It seems that this semester, people have decided that their friendship with me has progressed enough to ask me for "favors," "bang yi ge mang." Suddenly, left and right, people are introducing me to their neighbor's son, their friend's friend's son, or asking me to help out at their prep school. They all "just" want to "be my friend." But in reality, they want me to help them with their English for free. Don't they ever think about other people's time? That people might have other things to do, or that if we English speakers helped all of our "friends," we'd be working 24/7, listening to painfully broken English ALL THE TIME. I wonder if, partly, it's because Chinese society is composed of very self-centered, me-driven people. There's so many people (again, the same old excuse that explains all problems in China), so everyone just cares about him/herself, what she/he wants and how to survive and reach one's objective, regardless of what happens to other people. They just care about their need, or in the case of mothers, their child's need to learn English; they don't care about our feelings or the fact that we might be tired or that we might want to learn Chinese. We foreigners might as well just be inflatable, talking dolls or machines.

I come back tired and coughing from almost 6 weeks of traveling, first thing this lady downstairs from my apartment asks is when I can go to her house for a meal. I say I'm tired, I have a cough, I have lots of laundry and cleaning up to do, maybe another day. She doesn't take no for an answer and finally gets me to go to her house. Surprise, surprise, her neighbor and her neighbor's son and the son's friend are there to "meet me" so they can practice their English. It' my vacation, for goodness sake! I'm sick and with a cough! I'm tired and worn out from travel, I have photos to upload and blogs to post. I have sleep to catch up on, and you all don't care and just want me to give free English lessons?! That is why I don't easily accept dinner invitations anymore. I recall a Chinese/cantonese saying that some meals are so hard to digest that the food passes painfully through the backbone; this was one of them. That lady still has the nerve now to keep asking me when I have time to go to her house again for a meal. I politely smile and say that I'm very busy. She doesn't get the message, or rather, refuses to listen. She asks why I'm busy, what I'm busy with. HELLO?! That's my personal business, we are not good enough friends for you to have the right to know. Yet, I politely tell her that I have to teach, prepare lessons, study Chinese, take practice tests for the HSK, train for marathon. Then she still asks me if I'm free Friday to go to her house (totally ignoring all I told her about being very busy),I say I have friends over for dinner, she asks what about Thursday, I say I also have plans. That kept her at bay for a little while, but I just don't know when she's gonna hound me again to go to her house to "eat a meal," with ulterior English-learning motives. It feels so dishonest and sly, like cheating my emotions and feelings. I put my heart into friendships, and they just want to use me. Friends in America are made for good company and fun times, not to be used for benefits. Friendships based on benefits are called transactions.

Earlier tonight, even an older student of mine asked me for "a favor." She wanted me to go to the school that she started and help give mock interviews in English to prospective MBA students. She called me right when I was eating dinner at 7pm, I hesitatingly agreed to help her out, and for almost two hours, I sat and listened to thirt-somethings speaking one at a time in really halting English. My eyes were getting crossed, I was losing focus and could only see the lips moving without any comprehension because it was so difficult to understand through their heavy accents. Goodness, I hope I don't get dragged into another one of these again. How can they get it past their conscience to ask mere acquaintances and ordinary friends to perform such big favors?

Also irksome is the way Chinese mothers here are so annoyingly overprotective. Sure, it's your only child, but an 18 year-old should be able to do everything by him/herself. They don't need mama to hover over and coddle them. They don't need their mothers to bother their friends' friends' friend's English teacher. College and graduate students should be even more self-reliant and independent. Goodness. Many of China's young people don't know how to think or do things for themselves because their mothers and teachers help them with everything.