These are fine... I am torn apart because my dog passed. I am grieving over my dead dog. My dog is worm food now, and I miss him. My dog is pushing up roses and he was my best friend. My dog has gone to the other side and I do not think we will end up in the same place... That was a bad dog, but I miss him like crazy

Yup! These sentences are great! But if you want to use the first one then you should say: "I'm so sad because of the death of my dog." i don't know why but to me it sounds better. maybe you can find a real teacher to explain it to you but this is what i think :D good luck :D

Dude, I am watching you automatically, you are talking about death and stuff all along. Everything is ok?