Once you are a member the scripture "Bad associations spoil useful habits" is droned over and over again.
You will hear this one more than a few times also . . . . 2 Cor 6;
14 Do not become unevenly yoked with unbelievers. For what fellowship do righteousness and lawlessness have? Or what sharing does light have with darkness? 15 Further, what harmony is there between Christ and Be´li·al? Or what portion does a faithful person have with an unbeliever?
While the sister may not have been telling a direct lie . . . association with any outside the congregation is only sanctioned under the guise of "leading them to salvation"
Any prolonged association with outsiders for purely social reasons is heavily frowned upon, and would probably eventually invoke some "personal counsel"
You're dealing with a high-control religion . . . a cult . . . cutting you off from any who might "wake you up" is a controlling tactic . . . even if it is presented as "protecting your spirituality" Read through the following list of cult charcteristics and see how many seem familiar. They are not anti-witness and are presented from a neutral source . . .