There is nothing in the Quran that suggests that a husband is allowed to beat his wife. She is to be honored and treated kindly, even when one no longer feels love in one's heart towards her.

Having intercourse with one wife in the presence of the other and where she can see is something that is undoubtedly prohibited.

1- It is obligatory for the wife to please her husband if he calls her to his bed. If she refuses she is sinning. 2- The wife whose husband harms her by having intercourse with her too much can agree with her husband on the number of times that she can bear. For more, pleasesee the detailed answer.