We put our baby down two weeks ago and I can’t move on

She started to form a bump on her upper right lip in early November. It started out small and we brought her to the vet right away. We have a cat and they play fight quite a lot. The vet was certain that the cat clawed her in the lip and it got infected. She was given a week of antibiotics, but it got worse. They put her under and took a small cell swab. The results were that it was likely a histeocytoma and wasn’t a cause for concern. She was given another week of antibiotics. It did not work. By this point her lip looked like raw flesh. We brought her back to the vet and she then informed us that it looks like an aggressive form of cancer. I was broken. They put her back under and took a tissue sample. The results came back that it was a malignant tumor. Her body scans showed that it hadn’t travelled to her organs. We tried a variety of medication to help her but we were told that due to the location of her cancer, there was nothing they could do, because “we can’t just remove her lip”. Understood. For a while she seemed to respond really well to her medication. The swelling in her lip reduced significantly, it started to scab over, and she seemed like she was making some good progress. Then after a while it started to take over again. It came back with a vengeance. We had her on a relatively high dose of gabapentin 3x a day, to help her with pain control. Her quality of life really started to dip. We were clear with our vet that we didn’t want to keep her medicated just to keep her alive. We put her down on January 10th. It was an at-home euthanasia with her vet doctor and vet technician. Our girl was comfortable with them both after all of our in and out appointments in the recent weeks. She was so relaxed as she took her final breaths. It was such a peaceful way for all of us to say our goodbyes. She would have been 11 years old next month. I miss her so much. She has been apart of almost 11 years of my almost 13 years of being with my husband. I cannot remember life without her in our lives. We’re finding it so hard to move on without her. Everything reminds us of her. Sorry for the short story. TL;DR my dog died because of cancer and I miss her so much