It's Always The Husband by Michele Campbell

In a small New England college town, three inseparable friends—Kate, Aubrey, and Jenny—navigate the complexities of their tumultuous relationships, both with each other and the men in their lives. As their friendship is tested by betrayal, secrets, and ambition, a tragic event from their past resurfaces, threatening to unravel their carefully constructed lives. When one of them is found dead, the investigation reveals that the bonds of friendship can be as dangerous as they are strong, leaving everyone to wonder if it truly is always the husband.