Here in the UK it is not illegal to be nude in public, especially on your own property. She could be prosecuted for voyeurism! They are expensive but you could buy a tall tree/bush to block the gap. We did that every time a house was built overlooking our garden (ours was one of the first). Now I'm totally screened with trees which block views from neighbours, including their upstairs windows.
worked all day yesterday in yard cutting grass, adding mulch and just cleaning up yeah not nude but today I laid out on back porch nude and sunbathed yeah some screening there than decided to walk out into backyard nude, it only the middle where I lack enough screening so I stayed on left side. it feels so great to enjoy my yard bare I really think laws to be more open to nudity in your own yard as long as your behaving I really don't get it.
well my neighbors behind are moving don't know what to expect I know her quirks but even though she sees me nude she doesn't call the police , when the new neighbors move in will they be cool with my nudity or not if they have kids I won't expose them to my nudity so tough call. my trees are growing good in that little section but still will be a while.