What is the difference between being alone and feeling alone?

There are times when we are by ourselves and we are content, and yet times when by oursleves when we are alone, and also feeling alone. To that point, there are times when we are with othersm, wither individualy ir in a group and yet we still feel alone. Have you ever felt alone while you with others? Have you ever tried to determine why you felt this way? What was the answer? Is there a difference between being alone and being okay, being alone and not being okay, and being with others and feeling alone?!? Is aloneness whether with others or not a state of mind and/or a derivative of our personality as a result of our experiences? How do we become okay with being alone with or without others… and accept that aloneness?