Major hugs. My dad died almost 4 years ago when I was 30 and it was... it still is a difficult process. The first year was a blur- don't make any huge changes during the first year, your body is shut down to some extent trying to process the loss. The second year the reality of the loss hits you hard! You'll most likely feel a huge range of feelings, not necessarily sadness but rages that you don't link to grief right away. It feels like being crazy at times. It's best to release the tears when you can- don't hold back too much. Being on too many psych meds just delays the grief, I find. It really helps to find a support group!!! Hospices offer groups for free. I also have a dad journal that I write in from time to time. Things will trigger grief attacks out of the blue, even years later, but it doesn't hurt as much and you can focus on good memories more. There are still times now that I get "triggered," like just this week they announced that they might have found a cure for the type of brain cancer that my dad died from. My dad died only 4 months after he was diagnosed and there was no treatment at the time, so I'm having grief issues.
Also, something that helped as I went through the process was to draw an invisible line in the sand; on one side was my life with this person and on the other side was my new life without the person, and stop comparing them! They are two different lives and you can't go back to your old life, so I found that's where I got into trouble/depression- when I would compare the two lives and want my old life back.
So, anyway, you'll deal with it forever, but you'll get better at it and the loss won't consume you
So sorry about your dad.
What's your grief?