Its never an easy thing to loose someone who has been in your life for an extended period of time, regardless if it was good to bad. I guess the important thing is that you told what you felt needed to be said.
I think that going to the funeral would be good for you. You may not regret it, but I think that you in a way owe it to someone to at least pay your respects.
Either way, I hope that all goes well.
J
