That's so hard. All I can think is, you were so blessed to have a great parent, and that wonderful parenting is now inside of and part of you! You are the same wonderful parent now yourself. That part of your dad will live forever and positively affect generations forever. That is huge.
But the grief part, it is so hard. I lost my dad way back when....yep, I still miss him sometimes, and he and I were not even as close as you guys were. But I always crave that Daddy presence in my life. Always. And you always will too. Nothing will be able to replace him. You'll find your way through the grief though, with tears and long naps and more tears, and memorial services, and journaling, or whatever helps bring you closure. Well, not closure, but peace.
Don't fear Monday, don't worry about being with the grief. As anyone here can tell you, being WITH the grief is the only way of getting through and past the grief. It's when we refuse to live with and feel the pain, that we get stuck. Cry as much as you can. Scale back your activities. Don't try to be superwoman. Just keep things simple, basic and pure, and let your emotions be felt, all day and night. I know it is normal to sometimes feel totally numb, too. It is confusing, because we wonder where our emotions are? I think it is a self-protective mechanism, to keep us from feeling more grief than our brains can handle.
My miscarriage last week, at the end of the first trimester, has taught me more about grief and its weird stages, than I ever wanted to know. Sometimes the pain is so sharp and sudden and awful, other times I just feel numb. I feel so damned empty. I do not feel happy yet. Except when I'm holding my other kids, or nursing my toddler. Just loving your kids, that will help you feel better, less empty, I think. I know it helps me, it fills me up. Loving them cannot replace your dad, nothing can, but it makes life seem more purposeful.
My heart goes out to you. You will survive this, you will find sunshine again in time.