I'm a big believer that nothing heals a wound better than mustering up all of your gumption and going back to the scene of the heartache. By having a new/good experience, it replaces the pain of the old memory. You will get through it, because we know we have.
I have had to deal with this in relation to DLR a couple times, including very recently. One of our situations was somewhat similar to yours - my husband's mother died the day before our December 2001 wedding at the GCH.
We got a call saying my husband's mother died that morning. Needless to say, no one could fly there, so we had the stress of arranging assistance from local relatives that couldn't come here to CA for the wedding. Instead of a honeymoon, my husband left to help with the funeral - on Christmas Day, too. Since his mom was terminal with breast cancer, it wasn't completely a shock. We had already travelled back to say our goodbyes. Therefore, we just had to push on and celebrate on her behalf. The minister even took the time to write a touching speech to honor her in our ceremony. I still have that candle, too. Like I said, I still remember it, but the pain of the time has definitely faded with all of the good memories we have built at that hotel.
Perhaps also buying a candle with a fragrance that reminds you of him at the Illuminations store and lighting it for your father might help, as well!