Dealing with parents who want grandkids

Those who are child free or currently undecided, how do you deal with the guilty feelings of not giving your parents grandkids? I absolutely understand intellectually that it's my life so my decisions, but that doesn't stop me feeling guilty about grandkids (I'm currently on the fence and unsure about kids). I'm really close with my parents and they'd love to be grandparents and that hurts me. Has anyone here had to come to terms with this themselves?