IS HELPING OTHERS AN OBLIGATION?

Is helping others an obligation to us as citizens or as moral people? We may wonder. Am I really obligated to help that person, or do I just do it out of a sense of morality? As I’m standing by the roadside, about to cross the road, I see an elderly woman who seems to be hesitating at the curb. I decided to walk up to her and assist her in crossing the road. She smiles her brightest and walks away, thanking me. Now, as I’m on the other side of the road, I brood: What would have happened if I hadn’t helped her, let her be by herself, or just crossed the road by myself? She would've hesitated while crossing the road or would have received help from another person. But what would that have made me? A twat? Aloof? Austere?