Is happiness elusive because mostly in the mind?

 To a pen-friend I was fated never to meet.

I think of myself as searching for a happiness which seems destined always to evade me. I wonder if that is because the happiness I seek is imaginary. 

In our heads we can piece together imaginary animals which can be thought of, but which could never exist; like centaurs with the body and legs of a horse. Similarly we can imagine a day of sunny summer weather, then add in a wonderful meal, a punt, my charming companion a gifted pianist. But poor old reality stumbles along, completely unable to keep up with the fantasy. There are empty beer cans on the grass, a fly in the ointment, and the pretty girl does not want to make love with me. 

Should I be content with the dream, or learn to be content with reality, and its empty beer cans?