French language Q&A Forum

In "Personne ne croit en toi comme j'y crois", why "y" if y is standing for "en toi?" I thought y was for prepositional phrases beginning with à

Did some reading and it seems that if you are talking about 'YOUR own family' you use  EN FAMILLE.. if the activity excluded anyone BUT family. If you are talking about someone else's family or using a possessive pronoun (he ate with HIS family=AVEC sa famille/he ate with  the Jones family = avec la famille Jones/I ate with (my)  family= j'ai mange en famille. If this is correct why then did Monsieur Dulac not say "Alors, je vous souhaite un bon weekend avec ta famille". Is it because this interpretation is "a good family weekend"; a compound noun with EN;  rather than "a good weekend with family". Or is my reading /premise wrong?