Sex is a physical activity between 2 people that involves some physical contact and intimacy. It typically releases hormones like oxytocin and testosterone, which makes the people involved feel relaxed and relieved. Love, on the other hand, is an emotion that can cause feelings of anticipation, uncertainty, and anxiety. When two people are in love, they feel passionate and excited about being with each other, but this can also cause tension in a relationship. In summary, sex relieves tension while love causes it.