a fair-weather friend

fair-weather friend

Someone who remains a friend only when things are going well but abandons others during times of trouble or difficulty. I thought Allison and I had a strong friendship, but I learned she was just another fair-weather friend when she stopped talking to me after my divorce.
See also: friend

a fair-weather friend

someone who cannot be relied on in a crisis.
1998 Spectator The Americans gave up supplying gold on demand to other countries' central banks at £35 an ounce…when their fair-weather friends from London threatened to turn up and clean them out.
See also: friend

a ˌfair-weather ˈfriend

(disapproving) somebody who is only a friend when it is pleasant for them, and stops being a friend when you are in trouble: I really thought she’d be here to help me, but it seems that she’s just a fair-weather friend.
See also: friend