The Realms of Gold by Margaret Drabble

Frances Wingate is one of England's most renowned archaeologists, having recently unearthed a lost city in the Saharan desert. On the outside, she appears to have it all. But beneath the surface, she is struggling to deal with the demands of children and family, as well as a tumultuous, on-again, off-again romance with a married historian. Frances throws herself into work and travel, but when a tragedy forces her to return to England, to the flat countryside of her forebears, she discovers some surprising connections that offer her a chance to start again.