Tammy, just as Raven depends on you for food and affection, she depends on you for the most difficult of decisions, too. The decision weighs so heavily apon you, but you of course would never want her to be in pain.
Raven had the best possible person. You helped her through her separation anxiety, through abdominal surgery, through the heart worm problem. These are major events, and you have been an incredible owner/friend.
You try so hard to protect and ensure survival, and now your decision goes against all of your instincts. Its so difficult, but you are doing all of the right things. Pain management is key. Playing and having fun and conducting yourself as normally as possible will make both of you have more fun together.
Be strong. Be positive. You are lucky to have the wonderful relationship that you have together!
My best wishes go to both of you!