The world is full of people who manipulate and try to take advantage of others. It is so because much of humanity lives in the selfish mode. The degree may be different but the tendency to place one’s own interest even at the expense of others is fairly universal. Manipulativeness is only an extension of this tendency. So if one tries to stay away from those who manipulate one may well end up finding oneself almost alone.
What one needs to do is to draw clear boundaries and refuse to be a puppet to someone’s demands. Our choices and actions actions should not be dictated by what others want or expect from us but on what is truly the right thing to do with regard to the goals one has placed before oneself. Sometimes there is almost an unconscious need to get appreciation from others which leads to our trying to please them. This makes us vulnerable to be manipulated. Of course we should do good and be helpful but not with the idea of getting appreciation but simply because it is our true nature.
So the best thing to do is to stay focused on your goal. Have goodwill and kindness towards all. But if people start taking undue advantage of your goodness then draw a line and learn to say No.
Affectionately,
Alok Da