I once asked a certain person why she never said much when someone she knew personally left her jurisdiction, even when it was obviously a painful situation (e.g., they joined a group that considered her own group to be graceless). She told me that the reason was that a bishop had once given her very good advice. Don't judge people when they leave, don't judge people when they come back. That is to say, don't make a big fuss about them leaving and condemn them for leaving your own group, and then if they ever come back don't try to make them feel guilty. I'm not so sure whether she would extend that to Protestantism, but it is certainly good advice! Having had similar difficulties, I guess I can sympathise. Just make sure that your decision is based on God's will; don't ask "can I stand to be around these people?" but ask "am I going to displease God by doing this?" That's my own view, anyway; that's what I asked myself I mean.