I would choose good mental shape. If you lose your mind by way of Alzheimer's disease, for example, then it doesn't matter what kind of physical shape you are in. However, I think that being in good physical and mental shape go hand in hand. A strong mind and strong body go together. For example, if you are mentally sharp then chances are that you eat well, sleep well, exercise, and take care of your body. As far as relationships goes, it depends on whether you are introverted or extroverted. Extroverts would go crazy without relationships.