Estradiol For vaginal atrophy after breast cancer. Is it safe?

I have developed severe atrophy 25 years after estrogen receptive breast cancer. Did chemo, radiation and 5 years of Tamoxifen. I was always told NO estrogen. I am experiencing extreme pain and bleeding so sexual intimacy is impossible. I also have been diagnosed with Lichen sclerosus. I am 65 years old. My gyno has prescribed Estradiol vaginal cream 0.01%. I am told the new view and trials say is it is safe for breast cancer survivors. Anyone been down this route or had their gynecologist say this? I really want to try this for quality of life with my husband but I am also very scared.