I think this song is about putting on a mask to cover up what you're really feeling.
"I'm keeping inside, living in my mind..." is like bottling everything up inside, not being open or sharing your thoughts, feelings, dreams, or troubles with those around you.
When you're alone, with your own thoughts, you're "living in your mind"... and then when you go back out into the world, you put on a happy face saying "I'm fine"... hoping to convince yourself that you really are fine, even if sometimes, you aren't.
I think this song is about putting on a mask to cover up what you're really feeling.
"I'm keeping inside, living in my mind..." is like bottling everything up inside, not being open or sharing your thoughts, feelings, dreams, or troubles with those around you.
When you're alone, with your own thoughts, you're "living in your mind"... and then when you go back out into the world, you put on a happy face saying "I'm fine"... hoping to convince yourself that you really are fine, even if sometimes, you aren't.