既来之，则安之

jì lái zhī, zé ān zhī

[since we are here, we may as well stay and make the best of it; now that we have come, let us stay and take the rough with the smooth; now you are here, you'd better stay; since this is so, it's better to accept it and enjoy it] 既已来此, 那就随安于此

他果然既来之, 则安之, 我也只得因居之安, 则资之深。 --《儿女英雄传》