I can understand it’s a difficult decision. My cancer is TNBC so stopping Vagifem was never a consideration. My team does however support ER+ women using it. I originally went on it about 7 years after the menopause when vaginal lubricants were no longer controlling my symptoms. Essentially anything would cause a small hairline tear making intercourse impossible and even touch something that had to be approached with huge care. It made a world of difference for a few years, although the problems have gradually came back to some extent as I have got older.
It’s a topical application, very little gets into your bloodstream and the Tamoxifen should help stop that anyway. It will get worse and could also lead to frequent UTI infections. Quality of life matters too and I know I would personally choose to use it with my level of vaginal atrophy if I developed an ER+ cancer.