I'm so very sorry for your loss. Losing a loved one is extremely difficult. You really do have to fight to get through each day, sometimes each hour when your grief is overwhelming. I can empathize with you a bit since my situation has some similarities. I've lost 4 members of my family in the past 4 years including both of my parents. We have, like you our childhood home and we need to find the courage to begin the process of letting go of it. My dad built it with his dad 60 years ago and raised our family there. 60 years worth of stuff, full of memories and we have to decide to keep or discard these things. The task is daunting. I admire your courage for starting that very difficult task.
I think group therapy and/or one on one therapy is very beneficial too. I wasn't able to talk to anyone about my grief so I searched online for help instead. I found a website run by grief therapists called what's your grief dot com. Loads of helpful information on that site as well as lots of podcasts. I was able to listen to the therapy podcasts while at work and they helped me tremendously. I listened everyday for weeks and learned so much about coping with grief. You may want to look at that website to see if it can help you too. Hey free therapy is always a good thing isn't it?
Sounds like your Dad was a really wonderful man. I'm sure he will be missed terribly by all of those that loved him. Take good care of yourself. I don't believe it ever goes away completely, but with time it will become a bit easier to cope with your grief.