Lower levels of oestrogen don't just affect the vaginal mucosa. They affect the skin of the vulva, perineum, rectum. That whole area. I used Vagifem (topical oestrogen tablets placed in the vagina) for a couple of years but it wasn't until I started taking systemic oestrogen (patch, spray etc) that I felt truly comfortable again.
I expect that topical oestrogen cream applied directly to the problem areas would help too.
Anusol is just treating the symptoms. While you might be more comfortable in the short term, this is a hormonal issue that will only get worse if it's not treated. The gold standard treatment is to replace the oestrogen you've lost.