Dream about my dead dog?

My dog died the end of april.And i rly miss her because i had her for 11 years..and im 14.Anyways..i had a dream that it was night and i woke up.So i got up and looked out the window in the front room.Then i went to the kitchen (it rly dark) and i saw something white lieing down looking up at me that looked like my dog.And it was.So i picked her up and petted her (it felt real,and i think i was sorta controlling my dream)...and she wagged her tail,and seemed fine.Then i started thinking,shes dead and shes right here,fine,and im petting her...she seemed so happy to see me..then i forced myself to wake up..so then i actually woke up..and i was a little creeped out,but now i feel rly sad.Like she was so happy to see me,and i just left..i mean i could even feel her fur when i petted her,it was that real. Anyways..what does this dream mean?