It may have been only a few hours since you first got the news that someone you love is gone, permanently, from this earth. Your knees may still be weak and your hands still numb. You may have already cried the ugly cry, or you may still be waiting for it to hit you.
It may have been days by now, or weeks even. You've gone to the funeral or sent flowers from across the country in your stead. You've read the obituary online more than ten times, and you've left a comment on the online guestbook, and you've lit a virtual candle.
It may have been years now. You've navigated holidays and anniversaries somewhat successfully, trying to stay in the moment without getting caught in the tangled webs of "should bes" and "what ifs." But it's there, this gaping hole in your tradition, where that person once was but no longer is.
My advice to you is this: Cry those buffalo tears.
Mourning is the ultimate compliment you can give to someone who has affected your life so beautifully. It's the goal, if you think about it, to mean so much to someone in this life that they grieve your absence once you're gone. Allow yourself to give them that.
Then search your memories of them for what it is that they gave you in their time here-- courage? a love of classic cars/comic books/astronomy? an extremely long list of great advice that got you through some really dark times in your life? They inevitably instilled something in you that was meaningful. Find some way to continue on this legacy of theirs in your own way. Continue to go to car shows. Watch a meteor shower in the middle of the night with your favorite tiny human from a blanket in your driveway. Take the time to really listen to that friend who feels like this life is meaningless.
The truth is, most of us won't make it into the history books. Future generations likely won't know my name, or yours, or theirs. This is the best advice I can give for mourning: continue living, and don't allow their death to be the end of their mission.