Funerals are for those that are grieving. If you don't think it will aide in your grief, then I don't think you're obligated to go. Your friend is gone and will have no feelings one way or the other. If it's looked down on in your social circle, maybe explain to them that this is how you're dealing with it. You get to choose how to grieve and no one, not me or any of these other dipshits, gets a vote in how you do it.