I'm ~ier when... は、ふたつのことに比べるときに使うと便利です。
I would be happier when we meet after not being able to meet for a long time (than I would be if we are able to meet right away.)
二番目の表現は同じようなときにつけますけど、使う方が違います。
Meeting when we haven't been able to meet for a long time would make me feel happier.
もし想像しなくて現実に言えば would とhave been のかわりに be動詞になります。
I'm happier when we are...
Meeting when we aren't...
など
The happiness we feel when seeing each other after a long time of being apart is greater than the happiness of seeing each other whenever we want.
The happiness we feel when seeing each other after a long time of being apart is greater than the happiness of seeing each other whenever we want.
ちょっと長いので、小さく切って説明します。
The happiness we feel 私達が感じる嬉しさ
when seeing each other お互い会う時
after a long time of being apart 離れた状態が長く続いた後
is greater than 〜は〜より大きいです
the happiness of 〜の嬉しさ
seeing each other whenever we want いつでも好きな時に会うこと
逆にこれをなおすと:
いつでも好きな時に会うことの嬉しさより、離れた状態が長く続いた後にお互い会う時に私達が感じる嬉しさの方が大きいです。