I hope this doesn't upset anyone or sound utterly ridiculous. I'm probably on the autistic spectrum somewhere which hopefully makes a difference when you read this. 
I have huge difficulty with funerals, parties, processions, weddings... occasions of this sort make me really upset and nervous and I find it very hard to stay in the room, I get panicky and feel sick and want to leave. I think I have a kind of phobia as it's a very physical response.
I have never wanted to have a funeral myself and won't expect anyone to come and watch when I get buried. However most of society seems to have other expectations around this sort of thing and I am afraid of offending people, well, it's turn up and be terrified, or don't turn up and upset other people, possibly. Mainly I have been asked to stay behind and feed the pets when my family has gone to other occasions like this, which I did gladly but felt maybe I should have gone with them.
My granny is dying and I expect she will have a funeral. I don't know what to do. I genuinely don't understand what they are for, or what I'm expected to do...or how for instance my parents might feel if I didn't go.
I don't want to do the wrong thing but it all makes very little sense to me, so if anyone can try and explain what it's about, why it matters, that might help me to judge what the right thing is.
I will talk to my parents of course too but they will only want me to feel OK and don't generally put any pressure on - but if it would be better for THEM if I go, I want to do it iyswim. So I need a straight answer from people who aren't involved, because mum and dad won't say what they prefer.
Sorry if this sounds a bit crazy, I am at the least very introverted, and have always been odd about stuff like this, so please humour me. Thanks x