No one is the same. Therefore not everyone will have the same heart as you. Just because you are a kind person and care about others does not mean everyone will be the same. People generally do not think the same way, so you can never assume that they are on the same page as you.
Do not get offended when someone doesn’t feel or treat you equivalent to the way you would. The only person you should worry about is yourself; other people do not determine your success. Try not to rely on people to have a kind heart and help you benefit in life because they probably won’t. Most people are selfish, and sometimes that is the way you need to be to get where you want to go. Your heart is the only one that matters.