There is one very important thing that people often fail to comprehend properly. That is learning to keep healthy boundaries.
While it is good to contribute your mind and energy into helping someone and doing things that brings benefit to those around you; it is even more important to learn to mind your boundaries and knowing when to say NO.
If you keep on giving and giving and giving, then it's only a matter of time when you will get exhausted and one day wake up to a cruel realisation that everyone has a different heart and won't react the same way as you do.
Remember, You can't pour from an empty cup.