I don't want you to feel bad. I don't want you to feel sad. I don't want you to feel unhappy. I can't let you remain unhappy.

I cannot not bear to see you under the weather.

我不舍得你难过 I hate to see you upset

how can i let you be grieved？

oh,man,this is really difficult,so much chinese is hard or even impossible to translate into english. maybe somethimes you can try the opposite way, like the sentence you mentioned. i would say: i always try to make you happy, or, be happy honey....!!!! difficult.