My wife and I left the ELCA a year ago for the LCMS. We still have friends in our old congregation and would never presume them less than faithful for staying with the ELCA.
One must follow one's conscience in all matters. The only caution I raise to them, and you, is be ever diligent in your beliefs and interaction with others. It is very easy to become lax and allow doubts or seemingly cohesive arguments creep in to ones beliefs. The heads of the ELCA have allowed Satan to play in their lot.
Mrs. Reb and I are staying in our ELCA church and will do what we can to remain faithful and influence others to do the same. Several individuals (usually ones who have converted from ELCA to LCMS) have regularly lambasted me and the ELCA. The nicest thing we have been called today is "brain dead."