you have to find out why he asked your family not to tell you th

1. he is planning to have a new family with his gf, and he is waiting for the right timing to let you know.
2. he is not sure whether this is just a temporary affair and will end sooner or later.

Don't talk to him directly. He will only be annoyed knowing that you have been informed.

Ask someone else to talk to him instead and find out his plans regarding you.