my grampas just died,he was my rock and my best friend.i need help on what to say..x

hi, my grampa died on tuesday morning after a battle with cancer. i was his main carer and then basicaly stayed with him in the hospice until the end. he was my rock and my best friend in the world. im ment to be speaking at his funeral on monday but im stuggling to find the right thing to say. maybe a little bit on how he was my rock then a poem-but i have found nothing that would be suitable. he was not religious so its hard to find a poem. please help if you can...thanx x freya x