Being nice is also painful because of the following problems:
1. Not appreciated.
2. Being manipulated or make used of.
3. Not achieving objectives.
4. Get into a lot of misunderstanding and dispute.
However, depending on mindset, it is still worth it for me. There are many times I vowed not to do anything that is related to human or people, because I was deeply disappointed with the response. Nevertheless, every morning I worked up and was recharged again, I want to deal with human being again. To me, it is worth it and that is the beauty which balances off the pain.
Therefore, it is appropriate to “eat like poor man, stay healthy” – Yin & Yang
Don't ever give up on other people, for they are also having the same pain as you would. You have the power to make a difference.