She's the One by Cathy Kelly

Sexy, lively, agony-aunt Dee can solve other women’s problems in her sleep. When it comes to her own, though, she’s as muddle-headed as the rest of us. If she could lose about two stone, life would be a bed of roses. But first she needs to build up her self-esteem . . .
Or is it Isabel?
Life has landed Isabel with a raw deal: her husband has just lost everything they own. Full of insecurity, she launches herself into the life of a single parent. She desperately needs to recover her self-esteem . . .
When the job of Women’s Editor is advertised it seems the perfect solution – to both their problems.