The internal obstacle and its history
Contemporary romance's primary challenge is that modern life removes the external obstacles that historically separated lovers, which means the obstacles must be internal: rooted in the protagonists' specific psychological histories rather than in their circumstances. Writing internal obstacles with genuine weight requires understanding them from the inside — not just that the protagonist fears abandonment, but why this specific fear, where it comes from, how it has shaped her choices throughout her life before the novel begins. The internal obstacle should feel like something the protagonist has built a whole life around managing, not something she picked up recently, so that dismantling it in the course of a romance novel feels like genuine change rather than simply a decision.