I find that usually relatives at funeral are keen for as many people who cared about them as possible attend. It is nice and comforting to see that she was liked and loved. So I would worry only about how you feel you could cope with it. You are in a position to choose. HTH.
I think I would go (and sit at the back so I could make a hasty getaway if it all got a bit much iykwim) I blubbed like a maniac at a funeral a couple of months ago and felt pretty bad at the time but ultimately am glad I went.