SAN FRANCISCO — People often say choose your friends wisely, and now there’s some scientific evidence that doing so can help your health. A new psychological study finds people with positive experiences in their close relationships appear to have better physical health. Previous research has focused on how relationship conflict or satisfaction can impact stress levels and blood pressure. Study participants also shared their experiences and feelings about their closest relationships, including positive and negative memories, every three days. People with more positive experiences than negative ones often reported less stress, better coping skills, and lower blood pressure.