my dad passed away from a rare blood cancer on march 2016 how do I deal with or get over grief any advice ?

You don't. My dad died 25 yrs ago and my mom died 2 1/2 yrs ago. I still cry for them when I think about them, as now I'm doing right now. :(

By realizing he is now out of pain.

When I lost my most beloved MOM to liver cancer and one of my most beloved sisters to leukemia, their deaths acted as spring board to find cancer cures.

Everyone deals with grief differently.
It is normal to st8ll be griev8ng.
It is only a problem if it is interfering with your day to day activitirs.
If it is, you would probably benefit from talking to a grief counselor

Do your best to move on and continue with old habbits and practices. Absolutely take time to remember and honor him but do not let those memories drown you. Keep your head up and keep moving however you can.

it's december. get on with it. get past it. he's dead and he won't be giving you those extra bucks.