What we live for, no matter what the higher-order purpose we think of, is all about seeking and experiencing the sensation.
The emotional sensations, the core “good” feelings that you (up to a certain degree) can deliberately choose to pursue are the magnetic force that of My Compass. For me, those are:
The fulfillment of the "this is it" moment. When I enjoy life as it is. When the present is all I have, and it is enough.
The feeling of moving forward, knowing that the mission is far away, even the direction, or what's at the end, is unknown; but I know I'm moving forward (usually more than I feel)
Serenity - trust that everything is fine, I'm doing fine. A big part of this comes from Life Running Digital Engine.