Breast cancer leading to liver mets

My sister-in-law was diagnosed with breast cancer in 2006 and had a masectomy, 8 months of chemo and 4 weeks of radiotherapy. She was told after that she had the all clear, everything had gone well and she would take tamoxifen. Then in january this year after pain and swelling in her side it was discovered the cnacer had spread to her liver. They weren't sure why the tamoxifen didn't work. She began a course of chemo and was scanned again 8 weeks later. Unfortunatley, it had continued to spread. She began another course and until now this seems to be working. They recently put a portacath in. Now it has been discovered she has blood clots in her neck caused by the portacath so it had to be taken out and she injects everyday with blood thinning drugs. The problem is this means she is having no treatment. We're all still devastated from the diagnosis, even though it was in january and this is a major blow. Does anyone know anything about this? Also, I don't want to be morbid, but how long can people live after the initial diagnosis? secondary liver cancer seems to have a poor prognosis, is this true? I feel I need to know but I would never ask. Thanks if anyone can help!