My grandma is sick in the hospital. My mom is with her. While I feel bad for my grandma I feel worse for my mom.
That is very understandable. You are recognising that your Grandma has had (presumably) a fairly long and full life and is reaching the time when sickness and deterioration are inevitable. Your mother, though, is still in the thick of it and needs your love and support much more.
She would be 90 in July. She's done well for herself. ☺