sam2 & benignuman, thanks for your input on my post. what you write is how the rambam paskens about permitting pressure on a bona fide maos alei case. but the mechaber rules against rambam on this that beit din isnt permitted and the poskim since consistently accept the mechaber. yes, even if it is a long time separated it still isnt permitted to force him against his will. the mechaber and rema dont differentiate when permitting coercing the husband regardless of time they have been apart. a caveat to that is that it she can demonstrate to beit din that she has a legitimate maos alei permitted to do societal pressure, but no more – and even cherem isnt permitted. as you said there are cases where he is obligated to give a get even though beit din cannot coerce him (or it will be a get meusa) but he will give din vcheshbon if he refuses and there are other cases, such as she cannot prove a valid reason of maos alei (eg she feels he isnt loving or nice enough), that if he doesnt want to give a get he is entirely within his prerogative under halakha to decide he wishes the marriage to continue – and her leaving him regardless of lenth of time does not mean he has any obligation to give a get if he earnestly wishes to remain married. the ravvad in yerushalayim and rav eliashev write strong words against beit dins that apply pressure when it isnt permitted and they write their doing so causes mamzeirus in the world. since this is an issue with catastrophic consequences if a get meusa is used to remarry the poskim are very stringent in forbidding relying on the rambam to permit coercion by maos alei.
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