Not so good—He's in a better place or Just be happy he isn't in pain anymore。
不要说：他去了更好的地方或开心点，他不再痛苦了。

These things are always so well-intentioned, but ouch! The place the griever wants him to be is with her, no matter how much pain he was in or how difficult the caregiving was．
这些话的初衷的确是好的，但是悲痛者还是希望至亲就在自己身边，无论至亲有着什么样的痛苦或者无论照顾起来是多么的麻烦。

Better—You must miss him terribly.
不如说：你肯定十分想念他。