Shayla:

May I lie to save my friend’s feelings?

Responsa:

Simply saving your friend’s feelings is not a worthy enough cause to positively lie. For instance, you may not say “What a wonderful hat!” if you find the hat atrocious.

However, you may omit saying anything, and allow the person to assume anything they like as Hashem did with Abraham.

• Genesis 18:11-13 HCSB Abraham and Sarah were old and getting on in years. Sarah had passed the age of childbearing. (12) So she laughed to herself: "After I have become shriveled up and my lord is old, will I have delight?" (13) But the LORD asked Abraham, "Why did Sarah laugh, saying, 'Can I really have a baby when I'm old?'

The Lord God did not quote ALL of Sarai’s statement. He left out the fact that Sarai thought Abraham was too old to have children.