You make me happier than I ever thought I could be. If you let me, I'll spend rest of my life trying to make you feel the same way. 你给了难以想像的幸福，如果你愿意，我愿意用我的一生让你感受到同样的幸福。
spend v. 花费；浪费；度过；用尽（气力等）
The average spend on higher education was 55 pounds per head.