Definition
This idiom is used to sarcastically express that someone who claims to be your friend is actually behaving in a way that is harmful or unhelpful.
I thought he would help me, but he made things worse instead. With friends like him, who needs enemies?
She was talking badly about me behind my back. With friends like her, who needs enemies?
You knew I was in a hurry and you deliberately delayed me. With friends like you, who needs enemies?