Please accept my deepest sympathy on the loss of your mother (and grandmother). No matter how old we are, it still hurts to lose our mom. I have personally found comfort in the words at Acts 24:15 where it tells us, "There is going to be a resurrection", and that soon God will "wipe out every tear" from our eyes. (Rev. 21:4) I'm also looking forward to seeing the fulfillment of Psalm 92:14, "Even in old age they will still be thriving; They will remain vigorous and fresh".
You have my sincere condolences while we patiently wait for that day.