I am so sorry to welcome you to GT in this manner, as so many have said before me.
What my vet told me when my first girl Scarlett had osteo was that when it came to the point that we were having more bad days than good days, that is how I would know. Due to her age, we had been treating her for arthritis until we did the x-rays to confirm that it was osteo. When the x-rays confirmed the osteo, I set the date right then for my vet to come to the house to let her go in 12 days. While he said that we might have more time, I didn't want her to suffer. We had been dealing with her leg being sore for two months at that point, she was very old and I just couldn't bear the thought of her hurting. I truly believe that a day too soon is preferable. I spoiled that girl rotten for those 12 days and had a huge party for her on the last day with everyone she loved in attendance. It was all I could do for her. Then, I ran away from home and stayed with good friends. I know that not everyone can do that and I am truly grateful to the friends and their children who helped me through that first weekend without my girl.
Your girl is beautiful and the picture you shared shows a girl who knows, absolutely, that she is loved and treasured.