There seems to be a lot of apparent contradictions in the Ruth Story re: her status as a wife of Machlon, the time of her conversion etc.
Ruth first converts when she declares "ameich ami" to Naomi. Before that she is a 100% Moaviyyah. As such she never was Halachically married to Machlon, and was never related to Elimelech and therefore was really never part of the "g'ulah". The problems with this approach seem obvious, e.g. Why would Boaz or Ploni Almoni be obligated for a quasi Yibbum, if she never was legally Machlon's spouse?
Ruth had already converted to marry Machlon, therefore she was already a Jewess. This answers the question about Machlon's marriage but it poses even greater difficulties.
A. Who converted her? Given that Elimelech and his 2 sons would constitute an an invalid Beth Din, and who else in Moab would qualify?
B. Why would Naomi send her back to Moab? [same goes for Orpah] If she's already Jewish, that's an awful thing to do!
C. What kind of lessons re: Geirus can be learned by Ruth's poetic replies to Naomi? After all she was already Jewish?!
Shalom and Regards,