How do you help a parent that lost their parent

My mom's father lives in a different country he recently passed away.

I'm in denial he's my grandfather he was doing better we had hope of him coming here or us visitor him in the summer I have been strongly considering leaving and now he passed away.

I'm not sure what happened or if it's appropriate to ask but I want to know how he was okay in December but passed away in February I feel so heartbroken we didn't get to video chat and no one called to inform us so we could of video chat or called last few days or weeks or told about this I feel so sad.

He was my grandfather but first he was my mom's father and I know she loved him. How do I help her with grievances she must be so sad especially around Valentine's day of love about friendships, love family.

This is hard time as a few years she has wanted to travel to see him and we were just thinking of going.