My sympathy! The last three dogs I've had have been strays. Rambo had both internal and external tumors. Age and condition required taking him down. Missie was attacked by either a pit bull or coyotes. Fourteen puncture wounds. In-shock and vet recommended taking her down also.
Current one now is Roadie. When something happens to her (God forbid) she will also be cremated.
Do a search for The Rainbow Bridge. It will make tears flow but something to remember and cherish along with the memories of your Goldie.