Just because you aren't given the credit and haven't been recognised for your work doesn't mean you have to give up or stop. You don't always need credit, other people do not always have to know what you are capable of doing as long as you do.
This quote has helped me a lot of over the past few months. It's hard for me sometimes to let go of something that other people do and it makes me so angry, but then I remember this quote: " Take a deep breath. It's just a bad day, not a bad life.
And all I need to do is just breathe. Just breathe a prayer of thankfulness, for all You do. Just breathe a prayer of worship, an offering unto You. Just breathe a prayer, surrendering, "Thy will be done" anew. Then all I need to do is just breathe.