Elizabeth, I know that this time has to be difficult for you. Everyone needs to do what is good for them. I, on three ocassions, have had to put pets down. Each time, I held them when the Vet gave the injection to sedate them and would wait for the final injection, just to be with them. Each time I cried my little heart out, but felt good that I was there when they closed their eyes for the last time. You will know when you pet is suffering too much. I took my pets in early, to elimate a bitter and painful end, and that made me feel good about it. I didn't want them to suffer. My last pet was put down one year ago and I still think about her and have lots of pictures of her around. She didn't have to suffer too long. She had cancer of the tongue and was unable to eat or drink - I gave her water with an eye dropper until I found of the test results, then scheduled her for a Sat. trip to the Vet. I cried for days before and days after. It is the humane thing to do, but very difficult. I just know you will know when it is time. Good luck. Be strong.