How do i move on from something that happened 2 years ago?

It's kind of like a family member dying. This happened to me. My black poodle, Peppi, died of a broken hip. It happened on my dad's birthday and we had to put him to sleep. My dad was devastated. I guess you start to mourn very less the longer it is after the death. Then you start to remember the good times you had with Chacky and start to celebrate that he had a good life and now he is in a bigger and better place with other doggies to befriend. My dad always told me Peppi was waiting on the Rainbow Bridge for me, waiting for me to come home. Chacky is probably waiting for you too. And he's happy. Just let it go. You'll see him again.