How much do your feelings (actually) matter‪?‬ QSATA360

This question was inspired by a conversation with a friend who was arguing that, actually, our feelings don't matter. And to be clear, this is when we're feeling like an "impostor" -- when we feel like we're "not good enough" -- when we're not "worthy" or "able" or "capable" specifically. She believes that these feelings don't matter (not that she's immune either). But that they're simply roadblocks between where we are and where we're trying to go. So is that true? How much, in this case, do your feelings (actually) matter?