By remaining, you are implicitly saying that you can live with this system, or that it is at least better than any other alternatives.
There are some missing steps between "you can live with things as they are" and "therefore you should not attempt to change anything."
A moment's reflection will show that this nonsensical argument would apply to anyone anywhere at any point in history.
I don't agree with how every cent of my taxes are spent, but that's what comes with representative democracy.
Living with decisions you don't agree with comes with any form of government where you aren't dictator for life. That isn't special about democracy, representative or otherwise. What is special about democracy is that it expands the range of responses available when you disagree with something.
Democracy works when people advocate for changes they want. When enough people agree, change happens: in that manner, we approximate the greatest good for the greatest number.