I am so sorry about the loss of your father.
I took the passing of my mom whom I had seen to decline for years much harder than the passing of my dad who some years earlier had a heart attack.
Caring for somebody and seeing him getting worse nearly from day to day seems to create a special relationship.
Now is the time to be sad and to open yourself for these feelings which I am sure you had to suppress in the last years often enough.
And then you will find your life again.