Perhaps now that they too leave,However, I just want to 1et you happy. Allow me to the selfish.

或许他们现在正要离去,然而,我只是想让你快乐,幸福.请原谅我的自私吧!.
注:第一个too 我感觉应该是to哦.

Perhaps now that they to leave ,However ,I just want to let you happy.
也许现在他们要离开了，但是，我只是想让你快乐。原谅我的自私。

或许他们即将要离开，但，我只是想让你高兴起来。请允许我的自私。

现在也许他们也要离开，不过，我只想让你高兴。请允许我自私。