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I understand that a wife has a conjugal rights depending on the occupation of the husband (2 times a week, 1 time a week, on Friday night, one time a month, 1 time in 6 months, 1 time a year)
And that if she does not receive it she can demand a divorce
Does this include when the man gets old, (can not tie his sandal while standing on one foot) And physically can not perform his obligation.
Sources and/or details please, thank you